diff --git a/locales/en/apgames.json b/locales/en/apgames.json
index adcaf789..47d3a33b 100644
--- a/locales/en/apgames.json
+++ b/locales/en/apgames.json
@@ -5092,7 +5092,8 @@
             "TOO_MANY": "You may not place more than two tiles."
         },
         "product": {
-            "INSTRUCTIONS": "Players place, on empty hexes, two stones of either color. The only exception is on the first turn, where the first player places just one stone of either color.",
+            "INITIAL_INSTRUCTIONS": "At the start, place one stone of either color. Click current friendly stone to flip color, click again to empty hex.",
+            "INSTRUCTIONS": "Players place, on empty hexes, two stones of either color. Click current friendly stone to flip color, click again to empty hex.",
             "INCOMPLETE_TURN": "To complete the turn you need two placements.",
             "INVALID_PLACEMENT": "Unable to interpret the move notation: {{move}}.",
             "NORMALISE": "The move needs to be normalised. Try {{normalised}}.",
diff --git a/src/games/product.ts b/src/games/product.ts
index 6287fa27..f4cb09f8 100644
--- a/src/games/product.ts
+++ b/src/games/product.ts
@@ -264,7 +264,9 @@ export class ProductGame extends GameBase {
                 newmove = `${this.currplayer}${cell}`;
             } else {
                 const moves : string[] = move.split(",");
-                newmove = this.processMoves(moves, cell, this.currplayer).sort((a, b) => this.sort(a, b)).join(",");
+                newmove = this.processMoves(moves, cell, this.currplayer)
+                              .sort((a, b) => this.sort(a, b))
+                              .join(",");
             }
             const result = this.validateMove(newmove) as IClickResult;
             if (!result.valid) {
@@ -306,7 +308,11 @@ export class ProductGame extends GameBase {
             result.valid = true;
             result.complete = -1;
             result.canrender = true;
-            result.message = i18next.t("apgames:validation.product.INSTRUCTIONS", {count: nMovesTurn});
+            if (this.stack.length == 1) {
+                result.message = i18next.t("apgames:validation.product.INITIAL_INSTRUCTIONS");
+            } else {
+                result.message = i18next.t("apgames:validation.product.INSTRUCTIONS");
+            }
             return result;
         }
 
@@ -316,7 +322,7 @@ export class ProductGame extends GameBase {
 
         if (moves.length > nMovesTurn) {
             result.valid = false;
-            result.message = i18next.t("apgames:validation.product.TOO_MANY_MOVES", {count: nMovesTurn});
+            result.message = i18next.t("apgames:validation.product.TOO_MANY_MOVES");
             return result;
         }
 
@@ -325,9 +331,9 @@ export class ProductGame extends GameBase {
         try {
             for (const move of moves) {
                 currentMove = move.slice(1);
-                const [, y] = this.graph.algebraic2coords(currentMove);
-                // `algebraic2coords` does not check if the cell is on the board fully.
-                if (y < 0) { throw new Error("Invalid cell."); }
+                if (! (this.graph.listCells() as string []).includes(currentMove)) {
+                    throw new Error("Invalid cell.");
+                }
             }
         } catch {
             result.valid = false;
@@ -338,7 +344,7 @@ export class ProductGame extends GameBase {
         // Is is an empty cell?
         let notEmpty;
         for (const move of moves) {
-            if (this.board.has(move.slice(1))) { notEmpty = move; break; }
+            if (this.board.has(move.slice(1))) { notEmpty = move.slice(1); break; }
         }
         if (notEmpty) {
             result.valid = false;
@@ -347,7 +353,7 @@ export class ProductGame extends GameBase {
         }
 
         // possible to use moves() list to validate, but regex is (kind of?) fun
-        const regex = new RegExp(`^\\d[a-z]\\d+(,\\d[a-z]\\d+)?$`);
+        const regex = new RegExp(`^[12][a-z]\\d+(,[12][a-z]\\d+)?$`);
         if (!regex.test(m)) {
             result.valid = false;
             result.message = i18next.t("apgames:validation.product.INVALID_PLACEMENT", {move: m});