diff --git a/src/pages/VisProgPage/visualProgrammingUI/EditorWarnings.tsx b/src/pages/VisProgPage/visualProgrammingUI/EditorWarnings.tsx
index 554cc2c..2ff7397 100644
--- a/src/pages/VisProgPage/visualProgrammingUI/EditorWarnings.tsx
+++ b/src/pages/VisProgPage/visualProgrammingUI/EditorWarnings.tsx
@@ -1,25 +1,43 @@
-
+/* contains all logic for the VisProgEditor warning system
+*
+* Missing but desirable features:
+* - Global Warnings, e.g. not node specific
+*     - could be done by creating a global scope entry with GLOBAL as nodeId
+* - Warning filtering:
+*     - if there is no completely connected chain of startNode-[PhaseNodes]-EndNode
+*       then hide any startNode, phaseNode, or endNode specific warnings
+* */
 
 // --| Type definitions |--
 
 import type {FlowState} from "./VisProgTypes.tsx";
 
+
+export type WarningId = NodeId | "GLOBAL_WARNINGS";
 export type NodeId = string;
+
+
 export type WarningType =
   | 'MISSING_INPUT'
   | 'MISSING_OUTPUT'
+  | 'PLAN_IS_UNDEFINED'
   | string
-export type WarningSeverity =
-  | 'INFO' // Acceptable, but probably not desirable
-  | 'WARNING' // Prevents running program, should be fixed before running program is allowed
 
+export type WarningSeverity =
+  | 'INFO' // Acceptable, but important to be aware of
+  | 'WARNING' // Acceptable, but probably undesirable behavior
+  | 'ERROR' // Prevents running program, should be fixed before running program is allowed
+
+export type WarningScope = {
+  id: string;
+  handleId?: string;
+}
 
 export type EditorWarning = {
-  nodeId: NodeId;
+  scope: WarningScope;
   type: WarningType;
   severity: WarningSeverity;
   description: string;
-  handleId?: string;
 };
 
 /**
@@ -28,8 +46,9 @@ export type EditorWarning = {
  */
 export type WarningKey = { type: WarningType, handleId: string | null }; // for warnings that can occur on a per-handle basis
 
-export type WarningRegistry = Map<NodeId, Map<WarningKey, EditorWarning>>;
-export type SeverityIndex = Map<WarningSeverity, Set<{ nodeId: NodeId, warningKey: WarningKey}>>;
+
+export type WarningRegistry = Map<WarningId , Map<WarningKey, EditorWarning>>;
+export type SeverityIndex = Map<WarningSeverity, Set<{ id: WarningId, warningKey: WarningKey}>>;
 
 type ZustandSet = (partial: Partial<FlowState> | ((state: FlowState) => Partial<FlowState>)) => void;
 type ZustandGet = () => FlowState;
@@ -58,35 +77,37 @@ export type EditorWarningRegistry = {
    * unregisters a warning from the warningRegistry and the SeverityIndex
    * @param {EditorWarning} warning
    */
-  unregisterWarning: (nodeId: NodeId, warningKey: WarningKey) => void
+  unregisterWarning: (id: WarningId, warningKey: WarningKey) => void
 
   /**
    * unregisters warnings from the warningRegistry and the SeverityIndex
    * @param {EditorWarning} warning
    */
-  unregisterWarningsForNode: (nodeId: string) => void;
+  unregisterWarningsForId: (id: WarningId) => void;
 }
 
 // --| implemented logic |--
 
-export function editorWarningRegistry(get: ZustandGet, set: ZustandSet) : EditorWarningRegistry {return {
+export const globalWarningKey = (type: WarningType) : WarningKey  => { return {type: type, handleId: null}};
+export const globalWarning = "GLOBAL_WARNINGS";
+
+
+export function editorWarningRegistry(get: ZustandGet, set: ZustandSet) : EditorWarningRegistry { return {
   editorWarningRegistry: new Map<NodeId, Map<WarningKey, EditorWarning>>(),
   severityIndex: new Map([
-    ['INFO', new Set<{ nodeId: NodeId, warningKey: WarningKey}>()],
-    ['WARNING', new Set<{ nodeId: NodeId, warningKey: WarningKey}>()]
+    ['INFO', new Set<{ id: WarningId, warningKey: WarningKey}>()],
+    ['WARNING', new Set<{ id: WarningId, warningKey: WarningKey}>()]
   ]),
 
   getWarningsBySeverity: (warningSeverity) => {
     const wRegistry = get().editorWarningRegistry;
     const sIndex = get().severityIndex;
-
     const warningKeys = sIndex.get(warningSeverity);
-
     const warnings: EditorWarning[] = [];
 
     warningKeys?.forEach(
-      ({nodeId, warningKey}) => {
-        const warning = wRegistry.get(nodeId)?.get(warningKey);
+      ({id, warningKey}) => {
+        const warning = wRegistry.get(id)?.get(warningKey);
 
         if (warning) {
           warnings.push(warning);
@@ -97,24 +118,29 @@ export function editorWarningRegistry(get: ZustandGet, set: ZustandSet) : Editor
     return warnings;
   },
 
-  isProgramValid: () => { return true},
+  isProgramValid: () => {
+    const sIndex = get().severityIndex;
+    return sIndex.get("ERROR")!.size === 0;
+  },
+
+  getWarnings: () => Array.from(get().editorWarningRegistry.values())
+      .flatMap(innerMap => Array.from(innerMap.values())),
 
-  getWarnings: () => { return []},
 
   registerWarning: (warning) => {
-    const { nodeId, type, severity, handleId } = warning;
+    const { scope: {id, handleId}, type, severity } = warning;
     const warningKey = handleId ? { type, handleId } : { type, handleId: null};
     const wRegistry = get().editorWarningRegistry;
     const sIndex = get().severityIndex;
 
-    // add to registry
-    if (!wRegistry.has(nodeId)) {
-      wRegistry.set(nodeId, new Map());
+    // add to warning registry
+    if (!wRegistry.has(id)) {
+      wRegistry.set(id, new Map());
     }
-    wRegistry.get(nodeId)!.set(warningKey, warning);
+    wRegistry.get(id)!.set(warningKey, warning);
 
     // add to severityIndex
-    sIndex.get(severity)!.add({nodeId,warningKey});
+    sIndex.get(severity)!.add({id,warningKey});
 
     set({
       editorWarningRegistry: wRegistry,
@@ -122,18 +148,18 @@ export function editorWarningRegistry(get: ZustandGet, set: ZustandSet) : Editor
     })
   },
 
-  unregisterWarning: (nodeId, warningKey) => {
+  unregisterWarning: (id, warningKey) => {
 
     const wRegistry = get().editorWarningRegistry;
     const sIndex = get().severityIndex;
 
-    const warning = wRegistry.get(nodeId)!.get(warningKey);
-    // remove from registry
-    wRegistry.get(nodeId)!.delete(warningKey);
+    const warning = wRegistry.get(id)!.get(warningKey);
+    // remove from warning registry
+    wRegistry.get(id)!.delete(warningKey);
 
 
     // remove from severityIndex
-    sIndex.get(warning!.severity)!.delete({nodeId,warningKey});
+    sIndex.get(warning!.severity)!.delete({id,warningKey});
 
     set({
       editorWarningRegistry: wRegistry,
@@ -141,21 +167,21 @@ export function editorWarningRegistry(get: ZustandGet, set: ZustandSet) : Editor
     })
   },
 
-  unregisterWarningsForNode: (nodeId) => {
+  unregisterWarningsForId: (id) => {
     const wRegistry = get().editorWarningRegistry;
     const sIndex = get().severityIndex;
 
-    const nodeWarnings = wRegistry.get(nodeId);
+    const nodeWarnings = wRegistry.get(id);
 
     // remove from severity index
     if (nodeWarnings) {
       nodeWarnings.forEach((warning, warningKey) => {
-        sIndex.get(warning.severity)?.delete({nodeId, warningKey});
+        sIndex.get(warning.severity)?.delete({id, warningKey});
       });
     }
 
-    // remove from registry
-    wRegistry.delete(nodeId);
+    // remove from warning registry
+    wRegistry.delete(id);
 
     set({
       editorWarningRegistry: wRegistry,