Looks to me like you overwrote your config files as your photopost feature block no longer has the right data path etc.
I would suggest you check these things. Take note the vbulletin config.php file has all the info you need for cookie prefix and license number
1. Make sure your config-inc.php file of Photopost has the proper vbulletin license number for vb
not customer number
2. Make sure your config-int.php file has the proper server paths and urls for photopost forum and data directories etc. You should be able to turn on the enhanced integration then. Your white page indicates to me that your server path to vbulletin was wrong.
3. next in your vb
admin you can set your cookies like this and in photopost you may need to check the settings table of photopost entries 171-173 and make them match.
cookie path /
cookie prefix bb
cookie domain .wvbbts.org
Looks to me like vb
is set this way but Photopost can not be if it is not recognising the cookie. Make sure setting 41 in your photopost settings table says vb3 and not vb2