I am pretty sure that a plugin does not have the ability to affect a protected Server folder. The /tmp folder on a Server is a protected Server folder meaning that it does allow access to and writing to that folder, but does not allow changing anything about the /tmp folder itself such as permissions. It is possible though that something you have installed is blocking the access and writing to the /tmp folder from your dashboard. The obvious thing to try would be to deactivate all of your plugins except for BPS Pro. BPS Pro does not do anything related to a Server’s /tmp folder so this problem is not caused by BPS Pro.
I thought of something that you should check. Check your wp-admin folder and look for a php.ini file in your wp-admin folder. If you find a php.ini file then download it and open it to see what is in that php.ini file.
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