Is it normal to experience so much Rejects (Rejected untracked stratum share from pool 0)?
(5s):3.542M (avg):3.563Mh/s | A:68096 R:14848 HW:0 WU:5.7/m
ST: 2 SS: 0 NB: 76 LW: 1315 GF: 0 RF: 0
Connected to eu.clevermining.com diff 512 with stratum as user
[2014-04-21 20:22:01] Rejected untracked stratum share from pool 0
I get those rejects in 30 minutes of mining and only on clevermining.com pools. I found some older posts that the problem was fixed, but I guess the problem reappeared

The "Rejected Untracked Stratum Share" is what we call a fake reject. It's caused by a communication problem between the miner and the pool, and those shares are still accepted.
With my miner, will the same configuration that in all other pools are ok, I get a rejected of 75%
I am not able to fix this and I do not know what to touch.
I use gciminer and he configured automatically when i have selected my video card
So I returned to my previous pool.
There is no such thing as gciminer. If you are talking about guiminer, it is not compatible with scrypt, unless you are using guiminer-scrypt.