Is it possible to setup DGT Easy+ Gametimer for a 75' for first 30 moves, and 15' for the rest of the game? In the local chess club of which I recently became member we typically play games with time control described in the title. DGT's manuals are terrible so I do not know which DGT clock supports this time control. I tried to contact DGT regarding this, but nobody answered.

PS. someone please make a dgt tag.
My understanding is that this is sold as a budget / beginner's clock which does not support additional periods and so is not suitable for your needs.

You are probably better off springing for the DGT 2010 or DGT XL which I believe are both approved for FIDE competition. The 960 looks a bit flimsy for robust club use although I have no experience using it so it may be tougher than it looks.