If you have a cr2 that was previously made with 4.1, you can zero all the morphs and save that cr2 in place of the overwritten 4.1 cr2. I have both working fine in my install.
I also renamed both the cr2's and the png's as 41 and 42 instead of 4.1 and 4.2. One of my programs had trouble with the extra dot, can't remember which one.