Free version available, make a donation to access save/edit features. I took a punt and - far 60% intriguing/inspiring vs 40% baffling/infuriating - a lot of the controls fall into the "This changes the sound for Reasons" category, i.e. no way of predicting how moving them will affect things; at one point it stopped making any sound, and it took me about 10 mins to discover that setting RES to 0 with lowpass filter selected was the cause ¯\_(ツ)_/¯ . That said, there was something about fumbling away into the unknown and having to use just my ears to try and gauge what was happening that was weirdly liberating, and I got some quite nice thick aggressive textures from it that I don't usually get from exploring more 'normal' synths.

Never heard of Mr Kovalev before but apparently he's quite highly regarded in this field (PsyBOX, Ambitron and others).