Thanks for the fix! I was having the same problem in v1.0. This trick worked. Let me just add, though, that you only want to fix the idx value for the Kerbals with an "Assigned" status. If the Kerbal has a status of "Available" the idx is supposed to be -1! I initially went through and changed the value for all the Kerbals in my roster and found it didn't fix anything. I went back and compared the broken save file with an older one confirmed to work. Looking through the roster on the working one, I saw all the Available Kerbals still had an idx of -1. Once I changed it back on the broken file, it worked again!