About that nameofpractice.enc file; I thought it was encrypted? Is it encrypted or just password protected? If encrypted how would a rogue terminated employee access the data?
Anyone with sufficient computer smarts and familiarity with AC could download the installer from the AC website onto another computer. Then they could setup a dummy practice, and use the Restore program with the ".enc" backup file to reconstruct your entire practice on that computer, including eRx, assuming that person had a login and password.