Try loading the stock screen or aqua screen and see if you get the same results. If you do, then it's probably a CV setting.
What are the specs of the PC you're using? I've had two users in the last few weeks that have found that the larger toolpath requires a more powerful PC than the stock screens, and the 2010 Screenset won't run smoothly for them without turning off the toolpath.
Try running Task Manager and checking CPU usage while it's cutting.
The screenset itself should have no effect on motion. It should run identical to the stock screen or any other screenset. If it doesn't, there's a good chance that it's the CPU usage from the larger toolpath display.
I also read a post the other day that mentioned that using a high feedrate override can cause rough running in Mach3. In some cases programming for 100ipm with 200% override may run rough, but programming for 200ipm with 0% override works fine.