Row evolutions did not work on Actions => Pages (1 reply)

Hi all,
I have a small issue, If I try to open Row Evolution under Actions > Pages, the box "Loading Row Evolution..." opens, but nothing more happens equal how long I wait (10 mins.). I track 2 website with this Piwik installation, the one with 80 visitors the day works, the one with 250 visitors not. The bigger one have also a lot more pages the the smaller on.
Now another funny thing, the Row on the Dashboard works, but I need some special analysis. Any Ideas?? Thanks in advance.
Piwik Version: 2.5.0 RC3 (Same issue with the last stable)
Hosting: Host Europe Webserver Basic