diff --git a/src/kiri/mode/cam/app/init-ui.js b/src/kiri/mode/cam/app/init-ui.js
index 2f315981..ae2498ee 100644
--- a/src/kiri/mode/cam/app/init-ui.js
+++ b/src/kiri/mode/cam/app/init-ui.js
@@ -587,7 +587,7 @@ export function zPlaneSelect({ which, onselect }) {
     }
     clearPops();
     zPlaneStart(which, value => {
-        onselect(parseFloat(value));
+        onselect(parseFloat(value) / api.view.unit_scale());
     });
 }
 
diff --git a/src/kiri/mode/cam/work/export.js b/src/kiri/mode/cam/work/export.js
index f8bd0b2a..ee762acf 100644
--- a/src/kiri/mode/cam/work/export.js
+++ b/src/kiri/mode/cam/work/export.js
@@ -79,6 +79,8 @@ export function cam_export(print, online) {
             time: 0
         };
 
+    // console.log({ offset, origin, stock });
+
     function section(section) {
         append();
         online({ section });
diff --git a/src/kiri/mode/cam/work/op-level.js b/src/kiri/mode/cam/work/op-level.js
index 2f90b81e..ab1651d5 100644
--- a/src/kiri/mode/cam/work/op-level.js
+++ b/src/kiri/mode/cam/work/op-level.js
@@ -27,6 +27,9 @@ class OpLevel extends CamOp {
         let zBot = zTop - down;
         let zList = stepz && down ? util.lerp(zTop, zBot, stepz) : [ zBot ];
 
+        // ensure zList is descending
+        zList.sort((a,b) => b - a);
+
         if (share.ran) {
             console.log('skip');
             this.skip = true;
@@ -49,6 +52,7 @@ class OpLevel extends CamOp {
         POLY.fillArea(clear, 1090, stepOver, points);
 
         let layers = this.layers = [];
+
         for (let z of zList) {
             let lines = [];
             layers.push(lines);
diff --git a/src/kiri/mode/cam/work/prepare.js b/src/kiri/mode/cam/work/prepare.js
index 97443409..23f44a18 100644
--- a/src/kiri/mode/cam/work/prepare.js
+++ b/src/kiri/mode/cam/work/prepare.js
@@ -567,7 +567,7 @@ export async function prepare_one(widget, settings, print, firstPoint, update) {
             } else
             // otherwise move over before descending
             if (deltaZ <= -tolerance) {
-                if (debug) console.log('over before descend');
+                if (debug) console.log('over before descend', deltaZ, -tolerance);
                 layerPush(point.clone().setZ(printPoint.z), 0, 0, tool);
                 newLayer();
             }
@@ -636,7 +636,7 @@ export async function prepare_one(widget, settings, print, firstPoint, update) {
 
         // plunge safety catch
         if (deltaZ < 0 && !contouring) {
-            if (debug) console.log('deltaZ snap', rate, plungeRate);
+            if (debug) console.log('plunge safety', deltaZ, rate, plungeRate);
             emit = 1;
             rate = plungeRate;
         }
diff --git a/src/kiri/run/worker.js b/src/kiri/run/worker.js
index fa115dc0..086ac6c5 100644
--- a/src/kiri/run/worker.js
+++ b/src/kiri/run/worker.js
@@ -586,9 +586,9 @@ const dispatch = {
         const { process } = settings;
         const origin = settings.origin;
         const offset = {
-            x:  origin.x - (process.camOriginOffX ?? 0),
-            y: -origin.y - (process.camOriginOffY ?? 0),
-            z:  origin.z - (process.camOriginOffZ ?? 0)
+            x:  origin.x,// - (process.camOriginOffX ?? 0),
+            y: -origin.y,// - (process.camOriginOffY ?? 0),
+            z:  origin.z,// + (process.camOriginOffZ ?? 0)
         };
         const device = settings.device;
         const print = setPrint(newPrint(settings, Object.values(wcache)));