diff --git a/tx/cs/cs-snomed.js b/tx/cs/cs-snomed.js
index bf2f313..fd98901 100644
--- a/tx/cs/cs-snomed.js
+++ b/tx/cs/cs-snomed.js
@@ -659,6 +659,19 @@ class SnomedProvider extends BaseCSServices {
     }
   }
 
+  async incompleteValidationMessage(context) {
+
+    const ctxt = await this.#ensureContext(context);
+
+    if (!ctxt) return null;
+
+    if (ctxt.isComplex()) {
+      return "The expression is grammatically correct and the concepts are valid, but the expression has not been checked against the SNOMED CT concept model (MRCM)";
+    } else {
+      return null;
+    }
+  }
+
   async locateIsA(code, parent, disallowParent = false) {
     
 
diff --git a/tx/workers/validate.js b/tx/workers/validate.js
index 570e7da..36ba555 100644
--- a/tx/workers/validate.js
+++ b/tx/workers/validate.js
@@ -1005,7 +1005,7 @@ class ValueSetChecker {
     let tsys = '';
     let tcode = '';
     let tver = '';
-    let vcc = {};
+    let vcc = {}; // todo: VCC is an appendage, and useless. remove it
     if (code.text) {
       vcc.text = code.text;
     }
@@ -1066,6 +1066,9 @@ class ValueSetChecker {
         tcode = c.code;
         tver = c.version;
       }
+      if (!tver && ver.value) {
+        tver = ver.value;
+      }
       let cc;
       if (!ws) {
         ws = "";
@@ -1209,6 +1212,9 @@ class ValueSetChecker {
               }
             }
           } else {
+            if (!c.version && mode == 'codeableConcept' && prov.version()) {
+              c.version = prov.version();
+            }
             await this.worker.listDisplaysFromCodeSystem(list, prov, ctxt.context);
             let pd = list.preferredDisplay(this.params.workingLanguages());
             if (pd) {
@@ -1243,7 +1249,7 @@ class ValueSetChecker {
               msg(m);
               op.addIssue(new Issue(severity, 'invalid', addToPath(path, 'display'), baseMsg, m, 'invalid-display'));
             }
-            if (prov.version() && code.coding.length < 2) {
+            if (prov.version() && mode != 'codeableConcept') {
               result.addParamStr('version', prov.version());
             }
           }
@@ -1518,36 +1524,8 @@ class ValueSetChecker {
         if (loc.message && op) {
           op.addIssue(new Issue('information', 'code-invalid', addToPath(path, 'code'), null, loc.message, 'invalid-code'));
         }
-      } else if (!(this.params.abstractOk || !(await cs.isAbstract(loc.context)))) {
-        this.worker.opContext.addNote(this.valueSet, 'Code "' + code + '" found in ' + this.worker.renderer.displayCoded(cs) + ' but is abstract', this.indentCount);
-        if (!this.params.membershipOnly) {
-          op.addIssue(new Issue('error', 'business-rule', addToPath(path, 'code'), 'ABSTRACT_CODE_NOT_ALLOWED', this.worker.i18n.translate('ABSTRACT_CODE_NOT_ALLOWED', this.params.HTTPLanguages, [cs.system(), code]), 'code-rule'));
-        }
-      } else if (this.excludeInactives() && await cs.isInactive(loc.context)) {
-        this.worker.opContext.addNote(this.valueSet, 'Code "' + code + '" found in ' + this.worker.renderer.displayCoded(cs) + ' but is inactive', this.indentCount);
-        let msg = this.worker.i18n.translate('STATUS_CODE_WARNING_CODE', this.params.HTTPLanguages, ['not active', code]);
-        op.addIssue(new Issue('error', 'business-rule', addToPath(path, 'code'), 'STATUS_CODE_WARNING_CODE', msg, 'code-rule'));
-        result = false;
-        messages.push(msg);
-        if (!this.params.membershipOnly) {
-          inactive.value = true;
-          inactive.path = path;
-          if (inactive.value) {
-            vstatus.value = await cs.getStatus(loc.context);
-          }
-        }
-      } else if (this.params.activeOnly && await cs.isInactive(loc.context)) {
-        this.worker.opContext.addNote(this.valueSet, 'Code "' + code + '" found in ' + this.worker.renderer.displayCoded(cs) + ' but is inactive', this.indentCount);
-        result = false;
-        inactive.value = true;
-        inactive.path = path;
-        vstatus.value = await cs.getStatus(loc.context);
-        let msg = this.worker.i18n.translate('STATUS_CODE_WARNING_CODE', this.params.HTTPLanguages, ['not active', code]);
-        messages.push(msg);
-        op.addIssue(new Issue('error', 'business-rule', addToPath(path, 'code'), 'STATUS_CODE_WARNING_CODE', msg, 'code-rule'));
       } else {
         this.worker.opContext.addNote(this.valueSet, 'Code "' + code + '" found in ' + this.worker.renderer.displayCoded(cs), this.indentCount);
-        result = true;
         if (await cs.code(loc.context) != code) {
           let msg;
           if (cs.version()) {
@@ -1563,22 +1541,53 @@ class ValueSetChecker {
           op.addIssue(new Issue('information', 'informational', addToPath(path, 'code'), null, msg, 'process-note'));
         }
         await this.worker.listDisplaysFromCodeSystem(displays, cs, loc.context);
-        inactive.value = await cs.isInactive(loc.context);
-        inactive.path = path;
-        vstatus.value = await cs.getStatus(loc.context);
 
-        if (vcc !== null) {
-          if (!vcc.coding) {
-            vcc.coding = [];
+        if (!(this.params.abstractOk || !(await cs.isAbstract(loc.context)))) {
+          this.worker.opContext.addNote(this.valueSet, 'Code "' + code + '" found in ' + this.worker.renderer.displayCoded(cs) + ' but is abstract', this.indentCount);
+          if (!this.params.membershipOnly) {
+            op.addIssue(new Issue('error', 'business-rule', addToPath(path, 'code'), 'ABSTRACT_CODE_NOT_ALLOWED', this.worker.i18n.translate('ABSTRACT_CODE_NOT_ALLOWED', this.params.HTTPLanguages, [cs.system(), code]), 'code-rule'));
           }
-          vcc.coding.push({
-            system: cs.system(),
-            version: cs.version(),
-            code: await cs.code(loc.context),
-            display: displays.preferredDisplay(this.params.workingLanguages())
-          });
+        } else if (this.excludeInactives() && await cs.isInactive(loc.context)) {
+          this.worker.opContext.addNote(this.valueSet, 'Code "' + code + '" found in ' + this.worker.renderer.displayCoded(cs) + ' but is inactive', this.indentCount);
+          let msg = this.worker.i18n.translate('STATUS_CODE_WARNING_CODE', this.params.HTTPLanguages, ['not active', code]);
+          op.addIssue(new Issue('error', 'business-rule', addToPath(path, 'code'), 'STATUS_CODE_WARNING_CODE', msg, 'code-rule'));
+          result = false;
+          messages.push(msg);
+          if (!this.params.membershipOnly) {
+            inactive.value = true;
+            inactive.path = path;
+            if (inactive.value) {
+              vstatus.value = await cs.getStatus(loc.context);
+            }
+          }
+        } else if (this.params.activeOnly && await cs.isInactive(loc.context)) {
+          this.worker.opContext.addNote(this.valueSet, 'Code "' + code + '" found in ' + this.worker.renderer.displayCoded(cs) + ' but is inactive', this.indentCount);
+          result = false;
+          inactive.value = true;
+          inactive.path = path;
+          vstatus.value = await cs.getStatus(loc.context);
+          let msg = this.worker.i18n.translate('STATUS_CODE_WARNING_CODE', this.params.HTTPLanguages, ['not active', code]);
+          messages.push(msg);
+          op.addIssue(new Issue('error', 'business-rule', addToPath(path, 'code'), 'STATUS_CODE_WARNING_CODE', msg, 'code-rule'));
+        } else {
+          result = true;
+          inactive.value = await cs.isInactive(loc.context);
+          inactive.path = path;
+          vstatus.value = await cs.getStatus(loc.context);
+
+          if (vcc !== null) {
+            if (!vcc.coding) {
+              vcc.coding = [];
+            }
+            vcc.coding.push({
+              system: cs.system(),
+              version: cs.version(),
+              code: await cs.code(loc.context),
+              display: displays.preferredDisplay(this.params.workingLanguages())
+            });
+          }
+          return result;
         }
-        return result;
       }
     }
 
@@ -1863,13 +1872,14 @@ class ValidateWorker extends TerminologyWorker {
     let coded;
     let mode;
 
-    try {
-      // Handle tx-resource and cache-id parameters
-      this.setupAdditionalResources(params);
+    // Handle tx-resource and cache-id parameters
+    this.setupAdditionalResources(params);
 
-      let txp = new TxParameters(this.languages, this.i18n, true);
-      txp.readParams(params);
-      for (const item of txp.supplements) this.requiredSupplements.add(item);
+    let txp = new TxParameters(this.languages, this.i18n, true);
+    txp.readParams(params);
+    for (const item of txp.supplements) this.requiredSupplements.add(item);
+
+    try {
 
       // Extract coded value
       mode = {mode: null};
@@ -1902,7 +1912,7 @@ class ValidateWorker extends TerminologyWorker {
       this.log.error(error);
       this.debugLog(error);
       if (error instanceof Issue && !error.isHandleAsOO()) {
-        return this.handlePrepareError(error, coded, mode.mode);
+        return await this.handlePrepareError(error, coded, mode.mode, txp);
       } else {
         throw error;
       }
@@ -2304,7 +2314,7 @@ class ValidateWorker extends TerminologyWorker {
       if (!(error instanceof Issue) || error.isHandleAsOO()) {
         throw error;
       } else {
-        return this.handlePrepareError(error, coded, mode);
+        return await this.handlePrepareError(error, coded, mode, params);
       }
     }
 
@@ -2417,7 +2427,7 @@ class ValidateWorker extends TerminologyWorker {
   }
 
 
-  handlePrepareError(error, coded, mode) {
+  async handlePrepareError(error, coded, mode, txp) {
     let op = new OperationOutcome();
     op.addIssue(error);
     let p = new Parameters();
@@ -2434,6 +2444,15 @@ class ValidateWorker extends TerminologyWorker {
       }
       if (coded.coding[0].version) {
         p.addParamStr('version', coded.coding[0].version)
+      } else if (coded.coding[0].system) {
+        try {
+          let cs = await this.findCodeSystem(coded.coding[0].system, null, txp);
+          if (cs && cs.version()) {
+            p.addParamStr('version', cs.version());
+          }
+        } catch (e) {
+          // nothing. not interested.
+        }
       }
       if (coded.coding[0].code) {
         p.addParamCode('code', coded.coding[0].code)