Hello, ramps are handled by the S4DX module, all channels can have a ramp running at the same time without any slowdowns - code that handles ramps runs on each DMX frame anyway, just doing ramp change of 0.

Target value has 100 levels, but ramps are done with 8 bit resolution. Ramp times are changeable. Internally ramp time is represented as increase/decrease by one on every n-th DMX frame, or change by n every frame. It is also possible to send "raw" commands to S4DX module, to have fine control over ramps and their synchronization.