On my PC install was flawless, serial pasted with two leading spaces. After deleteing the spaces serial was accepted.
In Studio One it added 5% CPU usage during playback with one instance and no difference with two instances.
Windows 10 64-bit, Intel I9 10900K processor O.C. 5.0GHz, Asus Prime Z490-A mobo, 128Gb PC3300 Memory.
This was the latest Citizen Regen mix/master of Death Spiral. 84 tracks, buses and FX Channels. About 75 VSTs including 6 instances of Trigger 2 and 7 instances of Slate's Virtual MIx Rack. as well as Lurssen Mastering Console on the 2 bus. Buffers was set at 2048.