I am very impressed by the software and the UI: simple, clear, innovative. I do have a couple of suggestions:

The way "subtools" pop up near the "main tool" is smart and visually attractive. However i think if the toolbars always stayed in place instead of shifting up and down depending on which tab or tool is chosen, i think it would be easier to use the tools (one could almost use them blindly after a short while). The double fuction of clicking the tabs either for collapsing between tabs or switching tabs seems rather confusing (collapsing seems unnecessary at this point, i do realise this might change, once the number of tools increases).

I really like the fading out of the view control icons at the bottom of each view. For the rotate-view function i personally prefer the rotating to stop, when i stop the mouse movement. As it is, i have to switch between looking at the model and locating the cursor relative to the rotate-view icon. I guess this could be implemented easily as an option. The typical alt-middle mouse button shortcut to rotate-view would be nice to have as well, just in case i do have a keyboard available.

@Jon Banquer: (i haven't tried the program with a tablet yet) With the mouse the number keypad opens when i doubleclick the entry field. Is this different from the tablet behaviour?

Thanks for the great work,

Michael