Hi Luigi,
My sub has run out so please don't think this a request for support, more of a heads up. I just wanted to let you know I am still and consistently getting the issue with pagination. I simply can't get off page one. Some details for you:
Happening from around late Joomla 3.4ish. I know there was a fix in Joomla 3.4.2 or 3.4.3 almost the same was to do with pagination and filters. This is no filters active in Redj Errors or redirect. I'm using Enterprise 1.7.9.

I'm running 3.4.4. in Errors I have at least 10 pages probably upward of 100.
The issue happens on various sites and I have had confirmation from other users that they see the same issue.
We brought it up in JoomlaLondon meetup and the guy responsible for fixing the Joomla issue checked out Joomla's code there and then and suggested this is Redj issue.

My workaround of course is to show 100 instead of 25, that gets me the first 4 pages.
If I try to show all very often the system times out.

Hope it helps. If you want to look into our system, let me know and I'll arrange it.

Still loving ReDJ, thanks.
Gary