There is no account and no reset. A forgotten PIN cannot be recovered — not by you and not by us. That is what makes the vault private. Keep an encrypted backup, and remember its password somewhere separate.
No. FayVault copies what you add and leaves your photo library and files exactly as they were. Deleting the original afterwards is up to you.
Deleted items stay in Recently Deleted for 30 days, and restoring one puts it back in the folder it came from. After 30 days FayVault removes it for good.
Your vault lives on this iPhone. Deleting the app or resetting the phone removes its contents. Export or back up anything important.
The exported copy leaves FayVault's protection. Anyone with access to where you save it can open it. Your vault copy stays encrypted.