Well a word of caution is in order here. Unfortunately I could not pin down the use case as to how I managed to get the newer OR into this state but here is what occurred:
Opened an OR 15.03 file... Estes Leviathan from RocketReviews.
At one point I had apparently accidentally added a motor config but no motor.
I had a sim in place that repeated the motor from sim 1 (actually a nice touch since OR 15 would put in an empty sim for that which it just would not run).
At some point, and like I said I don't know how I did this, that last sim when run, filled in with all "N/A"s. So I removed it.
Then the other entries (there were three or four) started doing the same thing.
I removed all sims, and removed all motor configs, but no matter what I did any new entry would sim out with all "N/A"s in the field. The plot sheet was devoid of information.
Keep an eye out for this I'd say and try to be mindful of steps you used to get it into this configuration. I had copied all the sim files to a different directory for OR 22, but had accidentally opened the original (which is the one I trashed!). I was able to open the OR 22 form of the file in OR 15 and recover fine (after all the warnings etc.).
Back up early and often!