Check all forum connection information on step 1 of the install. You most likely do not have it entered correctly
Also on the last step of install when selecting ubbthreads also as Don suggested enter the proper table prefix usually by default is w3t_
This is why your photopost usergroups table did not get created as it could not import usergroups from the forum usergroups table. The import query failed.
I run a UBBThreads forum with all the products as well as the developer of Photopost. It most definately works right out of the box provided you enter the correct info.
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