I am merely telling you what I know to be a fact based on the coding. The install file includes whatever integration you are installing it for and in that integration file are both the functions that are called on install to create the usergroups table and popular it with groups from that specific forum. As long as all files are uploaded there should not be an issue if one is installing properly. You can see for yourself we clearly call these functions.
Code:
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That code is right out of our install file. We include pp-inc.php which includes the integration file your selecting to use and then we do the usergroups. That is all done on step 4 of the install.