When you select "Import" in the Main Menu of Quest for Glory 2, it should show you a list of files, which are the files in the directory it is currently looking in. These should probably be in the "C:\Program Files (x86)\GOG.com\Quest for Glory Pack\Quest for Glory 2\" folder. Paste the glory1.sav file in that directory, then in the Import menu scroll down until you find it.
If the contents of the import menu are not in the "C:\Program Files (x86)\GOG.com\Quest for Glory Pack\Quest for Glory 2\" directory, take a look in the "C:\Program Files (x86)\GOG.com\Quest for Glory Pack\" to see where they are.
As for mounting your flash drive, it is possible, but it will need you to edit the dosbox configuration files.
Find the "DosBox<game>.conf" file, where <game> is the game you will play, open it with notepad, scroll to the bottom where it should have a section [autoexec].
After the
"mount C ."
add
"mount I i:\"
This will mount the directory I:\ as the drive I in dosbox.
If you get an "Access Denied" error on saving the file, copy the file to desktop, modify it, then copy it back.
If you have any more trouble, ask.