Well this is a fun module. It's one half of the Dual Universal Slope Generator (CGS114) with an added button.
There are a couple very simple patches over on the wiki which are great and easy to normalize. First is that the DC output can be normalled to the CV input, so when nothing's plugged in the CV attenuator knob changes the rise/fall shapes. There can also be a toggle switch to loop the slopes, LFO style, which connects the "end out" to "trig in" jacks. I left that one out. The button I added is momentary, wired to +5V (with a current-limiting resistor), and normalled to the input jack.
In any case, one exciting thing for me is that this is my first time designing a toner transfer layout. A big upgrade from using sharpie. Shit can get a lot smaller and a lot more complicated, and I get a much better etch. It's a totally inelegant layout but I learned a ton. I'm using inkscape which is probably also inelegant for this, but I like it.
The schematic I used is on the page linked above.