That's really cool!

pretty slick ^^ and always better to have too many buttons than not enough lol

I always can add more buttons :D This is prototype. I'm now experimenting what button configuration I want.

DIY is good, I like such stuff. I wonder which software it requires?
But...
I have a cheap tablet without additional buttons/touchrings/so on. And I feel like I don't need anything like that: I have a whole keyboard under my left hand. It has much more buttons than say 4-6 on a typical tablet and I use the keyboard a lot.
Rotation in PS: a pen stroke with R key pressed. Hit Esc to rotate back to default position.
Scaling: Ctrl or Alt + Lower pen button(Pan/Zoom) + pen stroke.
And many other things are quickly accessible.

The only software it requires is profile switcher that let it know what program is launched and adjust active shortcuts set
With, say, only photoshop usage no software is required at all. It is recognised like USB keyboard + mouse

I need this because I work in 2 different drawing programs that have different non-configurable shortcuts for rotation.
Also it is fun :D
Also it sits to the left of keyboard, so only really most frequent actions are mapped there and I still have keyboard for the rest

Anyway, using a separate wheel for rotation must be fun.

I forgot to ask when it was new... Was that white stuff on the bottom Polymorph plastic? (Polycaprolactone)

Exactly )