When you convert your Cbus network to Cbus2 there is one thing I've seen a few times now. If you have Fixed Cbus Responses, and the CCLX file is automatically converted, when it comes time to save your file you might get a message that some Responses have errors.
The reason for this is that the old Cbus format is different to the new Cbus2, the CBus2 commands are slightly longer.
The easy solution to this is to Unfix all your Responses BEFORE you migrate to Cbus2. This way the Responses will be renumbered as and when required and you won't get to a situation where you manually have to go and fix each and everyone in an errored state.
Perhaps a future Comfigurator will check for this and warn us that the Responses need to be Unfixed or better yet, just tell us it will be Unfixed.