Lost default pathways

i have a pwer mac G4 0SX 10.4.11 and cubase SL 2.2.0

i have had this problem for about a month now and cannot do any work, so any help will be very much appreciated!
here is the problem written by an engineer who came to fix it, but couldn’t. he expalins it better that i would…

“What I think you did is accidently created a partition (or folder) on
your LaCie external HD, and then somehow made it so that Cubase
started treating this partition/folder as the default destination to
save files to and retrieve files from; and then deleted the
partition/folder you’d made. So now Cubase is looking for everything
in a non-existent location; so sometimes it can’t find your audio
files without being prompted, and it’s asking you to save your project
files in this non-existent location. This can be worked around by
opening each project file, locating the audio, and saving the project
(with Save As) back in the original location on the LaCie, replacing
the existing file each time; but it would be better if we could re-set
Cubase’s default file paths to look in the right place again for all
files; which I couldn’t figure out how to do…
now all these things happen…”

Prepare Archive- Save Project To New Folder