Thanks for feedback!
I have got same type of crsh many times (merge mesh). I have fixed it and updated link.
You can merge your own mesh in scene - in current state it should be closed and non - selfintersecting.
Use "Merge->Select mesh" and use pen/move/scale/rotate
in pen mode you need to click, in mrs - press enter to merge actually.
Andrew, great work! Many bugs with merge tool.
1. You can not undo scale,move,rotate operations.
2. Merge, select object, move mesh over sphere, press enter:
<a href="http://img241.imageshack.us/my.php?image=voxel01ry1.jpg" target="_blank">http://img241.imageshack.us/my.php?image=voxel01ry1.jpg</a>
<a href="http://img364.imageshack.us/my.php?image=voxel02fx4.jpg" target="_blank">http://img364.imageshack.us/my.php?image=voxel02fx4.jpg</a>
3. Scale, Rotate , Translate handles no do dissappear when you exit Merge tool.
4. Rotation reset: Merge tool , select mesh, rotate mesh, now select scale tool. It should not reset the orientation/rotation.
Hello Andrew.
I found a bug when a spline tube created with the snake tool self-intersect : a hole appear at the intersection.
Same here! It happens with the snake,spike,curves tool ( all 3 )
The 2d paint is nice but you should use another key instead of the RMB to set the plane (maybe Ctrl + RMB) . each time i zoom in the scene, with the RMB a new plane is set...
Totally agree. Also setting new plane with this tool only seem to work within the voxel space, it should work outside of voxel mesh( empty space).
FUN! 
is that gradient background in 3DC? i don't see any way to turn it on...