diff --git a/bun.lock b/bun.lock
index 95fd2c69..fc2f7c2f 100644
--- a/bun.lock
+++ b/bun.lock
@@ -104,6 +104,7 @@
         "motion": "^12.34.3",
         "nanoid": "^5.1.6",
         "tailwind-merge": "^3.5.0",
+        "three-mesh-bvh": "^0.9.8",
         "zod": "^4.3.6",
         "zustand": "^5.0.11",
       },
diff --git a/packages/core/src/systems/stair/stair-opening-sync.ts b/packages/core/src/systems/stair/stair-opening-sync.ts
index e4489631..2e478cd2 100644
--- a/packages/core/src/systems/stair/stair-opening-sync.ts
+++ b/packages/core/src/systems/stair/stair-opening-sync.ts
@@ -9,14 +9,6 @@ import type {
 } from '../../schema'
 
 import { resolveLevelId } from '../../hooks/spatial-grid/spatial-grid-sync'
-import type {
-  AnyNode,
-  AnyNodeId,
-  CeilingNode,
-  SlabNode,
-  StairNode,
-  StairSegmentNode,
-} from '../../schema'
 import { DEFAULT_WALL_HEIGHT } from '../wall/wall-footprint'
 
 type Point2D = [number, number]
diff --git a/packages/editor/src/components/tools/spawn/spawn-tool.tsx b/packages/editor/src/components/tools/spawn/spawn-tool.tsx
index c68cfa10..3bd1da3e 100644
--- a/packages/editor/src/components/tools/spawn/spawn-tool.tsx
+++ b/packages/editor/src/components/tools/spawn/spawn-tool.tsx
@@ -20,7 +20,7 @@ const SPAWN_ICON = (
   // eslint-disable-next-line @next/next/no-img-element
   <img
     alt="Spawn Point"
-    src="/icons/spawn-point.svg"
+    src="/icons/site.png"
     style={{ width: '100%', height: '100%', objectFit: 'contain' }}
   />
 )
diff --git a/packages/editor/src/components/ui/panels/stair-panel.tsx b/packages/editor/src/components/ui/panels/stair-panel.tsx
index 362c42aa..9ee03abb 100644
--- a/packages/editor/src/components/ui/panels/stair-panel.tsx
+++ b/packages/editor/src/components/ui/panels/stair-panel.tsx
@@ -294,7 +294,7 @@ export function StairPanel() {
           />
 
           {(node.slabOpeningMode ?? 'none') === 'destination' ? (
-            <MetricControl
+            <SliderControl
               label="Opening Offset"
               max={0.5}
               min={0}
@@ -340,7 +340,7 @@ export function StairPanel() {
 
       {(node.stairType === 'curved' || node.stairType === 'spiral') && (
         <PanelSection title="Geometry">
-          <MetricControl
+          <SliderControl
             label="Width"
             max={10}
             min={0.4}
@@ -350,7 +350,7 @@ export function StairPanel() {
             unit="m"
             value={Math.round((node.width ?? 1) * 100) / 100}
           />
-          <MetricControl
+          <SliderControl
             label="Rise"
             max={10}
             min={0.2}
@@ -360,7 +360,7 @@ export function StairPanel() {
             unit="m"
             value={Math.round((node.totalRise ?? 2.5) * 100) / 100}
           />
-          <MetricControl
+          <SliderControl
             label="Steps"
             max={32}
             min={2}
@@ -378,7 +378,7 @@ export function StairPanel() {
             />
           )}
           {(node.stairType === 'spiral' || !(node.fillToFloor ?? true)) && (
-            <MetricControl
+            <SliderControl
               label="Thickness"
               max={1}
               min={0.02}
@@ -389,7 +389,7 @@ export function StairPanel() {
               value={Math.round((node.thickness ?? 0.25) * 100) / 100}
             />
           )}
-          <MetricControl
+          <SliderControl
             label="Inner Radius"
             max={10}
             min={node.stairType === 'spiral' ? 0.05 : 0.2}
@@ -417,7 +417,7 @@ export function StairPanel() {
                 value={node.topLandingMode ?? 'none'}
               />
               {(node.topLandingMode ?? 'none') === 'integrated' && (
-                <MetricControl
+                <SliderControl
                   label="Top Landing"
                   max={5}
                   min={0.3}