I would suggest you upload a clean gallery code minus a data directory to the new server and dump the data directory from the old server in that directory and set permissions on all folders files based on the install directions. You would move the database tables either to the new database if those tables existed in your old vb
database or make a new database for photopost and restore those tables which ever works for you.
You can then do a clean install integrating into the new vb
install just make sure to use the photopost tables for the new install you will get duplicate errors no problem
You would also then after you do an install run the upgrade script and run any applicable upgrades if this was an older galllery install.
Once you do all this go back and complete the part of the install to generate the vb4 plugins.
There is a tutorial in the how do I forum on how to move servers but my response above is what I would do.