I updated to version 1.6.14 on MacOS. When prompted I replaced the current application (it asked do you want to replace the file, keep both or cancel). I then opened up the app and my vault is gone along with all my files.
Please more details. What do you mean with „gone“? Just not listed in the app anymore? If yes, did you try to re add it? If yes, please describe what you do, what the system does and what you expect shoul happen instead?
Maybe something suspicious in the log files?
Where was your vault originally located? Try searching your system for a file „masterkey.cryptomator“ or „vault.cryptomator“
Seems like the configuration file was overwritten during the update process. So Cryptomator has forgotten your vault path. Nevertheless it should be still on your system. Vault files are not changed/deleted during an app update.