Portfolio not centered, custom-css not working(?)

It was okay some days ago but not the problem appeared for all my portfolio items. why?

I’ve already worked it out a little more:
Everything’s fine when using ONE portfolio per page. After using two it will start to behave the strange way like mentioned above

I really need more than one portfolio per page or I have to request a refund, because I can’t use the plugin then.

Update:
This only happens when both portfolios having different configuration at “Grid alignment”. In my case one was centred one was right. It’s okay for me at the moment now, but in generally all portfolios should work with their own configuration!