Quote: "- will it be possible to take differents keys on the floor or on tables to open differents doors?"
Keys can be on any surface. They can open any door (you just tell the door which key opens it).
Quote: "- will there be some 'pushable' items (blocks, tables, chairs...) like in RTCW?"
Don't think so.
Quote: "- will it be possible to have some damage zones (like lava or toxic gaz where the player take damage)?"
Yes. Definately.
Quote: "- will there be lifts or moving blocks like in platform games?"
There are lifts.
Quote: "- if the player fall from a too high distance will he takes damage or die?"
Yes - the height at which damage is taken is customisable.
Quote: "- is the EA version for debugging purposes or will TGC asks people after its release what improves they wish?"
There is a bugtrack system, and you will be invited I think to report bugs at all times
Quote: "Everything is yes to your questions as logn as you an program :p"
You're wrong - you don't need to program for all of those questions. I've seen a number of answers by you saying things are possible by doing x y or z - but you haven't even used it yet