Installed 7.5 RC at two servers, installation was a little bit tricky, but the systems work without problems now.
At the first server I had a generally update problem, because I tested subscription before. See here:
The second one missed some PHP dependency for dokuwiki. Enable @stephdl -repo for update did the trick:
yum update --enablerepo=stephdl
@dev_team, @alefattorini and all other who did some work for it. Thanks for your great work