If you get this
Warning: mysql_fetch_array(): supplied argument is not a valid MySQL result resource in /home/tinastea/public_html/photopost/forums/vb3.php on line 25
Your issue can be only one of two things. I would suggest you rerun install.php and input the proper information.
1. You have entered the incorrect vbulletin database info on the config section under user database on Photopost Install
2. You did not enter the proper forum database table prefix on the next to last step of install where asked.
Your issue can only be one of these two things. It is up to you to determine which one is your issue here. Basically Photopost is not able to run queries against the vbulletin database. Both your vbulletin table prefix and database information is found in the vbulletin config.php file located in your forum includes directory.