Alright, well looks like this forum has low attendance (euphemism ^^), anyway it looks like I've solved this problem and I'll share the solution here, even if nobody will ever read it :-) What did...

Region : France Model : TL-WR710N Hardware Version : V1 Firmware Version : 3.14.9 Build 130419 ISP : Orange (ex France Telecom) Hello - and sorry for the loong post I don't know how to explain this...