diff --git a/js/kiri-worker.js b/js/kiri-worker.js
index b8860ccb..deed16b2 100644
--- a/js/kiri-worker.js
+++ b/js/kiri-worker.js
@@ -50,6 +50,8 @@ let dispatch = {
             position: position
         };
 
+        try {
+
         widget.slice(settings, function(error) {
             if (error) {
                 delete cache[data.id];
@@ -80,6 +82,10 @@ let dispatch = {
             send.data({update: (0.05 + update * 0.95), updateStatus: msg});
             last = now;
         });
+
+        } catch (error) {
+            send.data({error: error.toString()});
+        }
     },
 
     printSetup: function(data, send) {
diff --git a/web/kiri/lang/en-help.html b/web/kiri/lang/en-help.html
index 8e3c9bb9..c24a1a7a 100644
--- a/web/kiri/lang/en-help.html
+++ b/web/kiri/lang/en-help.html
@@ -31,12 +31,10 @@
         <button onclick="kiri.api.mode.set('FDM')">FDM</button>
         <button onclick="kiri.api.mode.set('CAM')">CAM</button>
         <button onclick="kiri.api.mode.set('LASER')">LASER</button>
-    <li>Select <button onclick="kiri.api.show.devices()">Device</button>
-    <li>Set slicing parameters in right panel
-    <li><button onclick = "kiri.api.function.slice()">Slice</button>
-        using settings from the right panel
-    <li><button onclick = "kiri.api.function.print()">Preview</button> GCode output
-    <li><button onclick = "kiri.api.function.export()">Export</button> GCode
+    <li>Select your target <button onclick="kiri.api.show.devices()">Device</button>
+    <li>Then <button onclick = "kiri.api.function.slice()">Slice</button>
+        <button onclick = "kiri.api.function.print()">Preview</button> and
+        <button onclick = "kiri.api.function.export()">Export</button> GCode
     <p>
     <b>Other ways to use Kiri:Moto</b>
 
@@ -91,21 +89,12 @@
             <tr><td><label>w</label></td><td>Wireframe</td></tr>
             <tr><td><label>delete</label></td><td>Delete</td></tr>
             <tr><td></td></tr>
-            <tr><td><label>arrow-left</label></td><td>Z Rotate CCW 90&deg;</td></tr>
-            <tr><td><label>arrow-right</label></td><td>Z Rotate CW 90&deg;</td></tr>
-            <tr><td><label>shift-arrow-left</label></td><td>Z Rotate CCW 5&deg;</td></tr>
-            <tr><td><label>shift-arrow-right</label></td><td>Z Rotate CW 5&deg;</td></tr>
-            <tr><td></td></tr>
-            <tr><td><label>arrow-up</label></td><td>X Rotate CCW 90&deg;</td></tr>
-            <tr><td><label>arrow-down</label></td><td>X Rotate CW 90&deg;</td></tr>
-            <tr><td><label>shift-arrow-up</label></td><td>X Rotate CCW 5&deg;</td></tr>
-            <tr><td><label>shift-arrow-down</label></td><td>X Rotate CW 5&deg;</td></tr>
-            <tr><td></td></tr>
-            <tr><td><label>option-arrow-up</label></td><td>Move Up 5mm</td></tr>
-            <tr><td><label>option-arrow-down</label></td><td>Move Down 5mm</td></tr>
-            <tr><td><label>option-arrow-left</label></td><td>Move Left 5mm</td></tr>
-            <tr><td><label>option-arrow-right</label></td><td>Move Right 5mm</td></tr>
+            <tr><td><label>arrow</label></td><td>Rotate 90&deg;</td></tr>
+            <tr><td><label>shift-arrow</label></td><td>Rotate 5&deg;</td></tr>
+            <tr><td><label>option-arrow</label></td><td>Move 5mm</td></tr>
             <tr><td></td></tr>
+            <tr><td><label>ctrl-click</label></td><td>Align face to bed</td></tr>
+            <tr><td><label>meta-click</label></td><td>of selected object</td></tr>
         </table>
         </div>