Cryptomator 1.4.x and 1.3.3 will be compatible. You can keep using 1.3.3 on 32 bit machines and sync the vault with other devices that are on 1.4.x.
5 GB files can not be added to 1.3.3 vaults on Windows, though. See this thread about the 4GiB file size limit in WebDAV.
I.e. you will most likely be able to add a 5 GB file on 1.4.x and open it on 1.3.3 but not the other way round.