changing user from subscriber to customer

Changing user from subscriber to customer causes our site some problems, i couldn't track it down so had our developer on it last night. It turns out its user's role, when i bulk upgrade people from subscriber to customer ( when they are just new & have not posted anywhere )  when they become customer & forum shuts down or won't load for them - it is like you see the header & footer & nothing in between ( like the plugin is de-activated )....

Our site I've been building is a private forum for graduates, there are 4.9 million graduates around the world , if people are bit hesitant they won't come & won't spread the word, so we want anyone registered we want them able to see & do most things without limitations, after a month or 2 with graduates signing up & posting we will revert it back to min 5 posts to do things . is this possible ? what options do i have if we want everyone who first registers to go straight to "customer" ??

we might actually request a quote in the future for some addons/ work once we have lots of graduates on the site, as we want this platform to above & beyond anything that is out there. I have seen this listed here for anyone who wants more features. 

I love wpforo forum , but it has its limitations in areas . would love to really be open source.