Is it possible or will things work fine if I replace the older GRUB4DOS version that UBCD4WIN 3.22 came with, with the latest version of GRUB4DOS? Or will this cause errors? The reason is I tested the new version files of GRUB4DOS by replacing them on the bootable USB key I made, and it corrected a lot of warning messages I was receiving and now I'd like to use that version permanently if possible using ubcd4winToUSB for my future USB keys. If anyone knows if this will cause problems when formatting and setting up the key let me know, thanks!

Do you get error messages?
Which error message do you get?

Yes, you may use a new version.
Old version did support // at menu.lst. New version maybe not.