Now for a few suggestions.
Please, if at all possible, make the knobs not respond to vertical and horizontal mouse movement at the same time. This is one of the most annoying things you can find in a graphical UI because nobody can move a mouse so precisely up and down that the left/right axis wont respond as well. As a result one axis keeps fighting the other and dialing in the desired value becomes a test of patience because you constantly have to compensate between the value changes that each axis makes.
The synth has PWM but no knob on the UI to control it. The only way to set a static PW is therefore to use the 'Constant' modifier in the modmatrix assigned to the respective osc. To have a PWM knob on the UI without altering its layout and dimensions, maybe you could make the Detune knob multi-purpose, so it controls the detuning when the Saw is selected and the PW when the Square is selected. (When the Triangle or Noise are selected it could simply be greyed-out since it does nothing with these sources anyway.)
It would be great if the user could choose a custom location for what you call the 'Home' folder. (Settings, Presets, Skins.) Right now it appears hardcoded to local appdata, which of course is on C: which many people want to reserve for the OS as much as technically possible. (So OS volume backups remain small and valuable application data remain safe on the data volumes should C: have to be wiped.) The simplest way to make this possible is probably having an .ini file next to the DLL which it reads upon startup to see where the Home folder is. Many devs do it that way and its great because unlike a registry entry it cant be lost with a OS fresh install.
The synth has such a nice sound, it just begs for some stereoizing. The simplest way to achieve this would be to give the oscs a Pan function. Another would be some form of Unison with selectable amount of voices and Spread capability.
Thats it for now, thanks for the synth, its a keeper.
