The database schemas between DFM 5.0 and 5.2 are different. Assume that backup/restore functionality is not going to work between releases.
While you can certainly install the new 5.2 and have it ready to go, I suggest you upgrade the existing one in place, then do the backup/restore cycle. Or if DFM 5.0 can run on 2012, transfer then upgrade. Either way - keep the versions the same during the backup/restore cycle.
Are you using the same name and IP ??, we used the same so we did not run dfm ssl setup cmd, just the one i mentioned before, if you changing name or IP yes, you should run this cmd on the new server and enter the info asked.
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