I can confirm TDAY's report. The inner wheel on my ShuttlePro is no longer working after I upgraded to Mach4Hobby 4.2.0.2914 either. I was using the previous version 27xx? and everything was working fine.
Daz, define what you mean by "setup the mpg in the mach config". I have the *********tlePro plugin enabled. But, I do see MPG0 through 9 (or so) in the Mach config. Is that what you're referring to?
The ShuttlePro has its own setup where you click a button on it and set what that button does. Moving both the inner and outer wheel doesn't bring up anything here though, so I can't use that to program the ShuttlePro.