AbeSurd

Re desirability of backing up the entire container file. This might depend on how big the file is and how often you want to back it up. Please note I said "I used to use SyncToy to sync the contents to another encrypted volume on another drive."

I haven't used VeraCrypt but I used to use TrueCrypt. As I understood it, the machine you use to try and access the TrueCrypt volume at the very least would have to have the TrueCrypt program installed on it. I imagine VeraCrypt would be similar. But I don't know. Re backup - yes that's my understanding. You'd need to open/decrypt the encrypted volume in order to backup its contents. Having done that I used to use SyncToy to sync the contents to another encrypted volume on another drive. Tedious!