No, the plugins are backwards compatible if the plugin authors use the format and style we give them. This was a major design feature from the first day we started to code mach4! Now if we add a feature that is new and they need the calls for it, yes it must be updated. But we are trying to do very little major changes like that anymore. Also know when we release we have run the code on 6 or more motion controllers and we have min of 2 solid days of testing that must be passed before it can be called a release. We have a few small issues we are looking at now in the screens. I think they are fixed but every time we find an issue the testing starts all over again from the beginning.
What motion controller are you concerned about ?