I had seen your earlier post, but had not commented because, for my particular situation, I had found an alternative fix. This solution does not go to your specific request but has worked for me.
I do support your request. And had raised the same several years back when I commissioned my 8’ Exploradome using their gearmotor with rack and pinion, along with the Lesvedome to drive it. In my case, when the Lesvedome system signaled “move” to the Velleman K8055 and relays, it was full power and speed instantaneously. This created a large vibration throughout the OBS which I suspected was damaging the quality of the image subs. At that time I was unable to find a way to limit dome movement to between subs.
As an alternative I added a CKMX066 PWM 12VDC 30AMP motor speed controller to the circuit. The device was infinitely variable and I was able to dial it down to minimize initial startup torque and rotational speed. Both of which greatly reduced the amount of vibration driven into the scope and mount.
Your dome is substantially heavier, and the operation is no doubt very different.
But food for thought. Hope it helps.