yes coppermine would if they where integrated
the userid's will change because you used
vb impex script to import your forum data so thats why things change.
You do not need to start over because no matter what you do your going to have the same issue.
You will need to do your smf to
vb import
Your
vb is setup you then install photopost
You then import the coppermine data to photopost using the import script in the importers forum.
You then after the import etc is all done you download a script called userfix from the importers forum to help correct userid's when switching to
vb.
That script attempts to repair the userids if it can. like I said its not foolproof here as we are trying to redo things because of changes done by your switch and import.