if you search the forum there have been plenty of posts on this issue - the door pocket water ingress happened on mine -have you got the standard front speakers in your car? (as upgrading them can cause issues).
i had standard speakers and found that the water was leaking in through the gap (hole) that the speakers are fitted in - so after speaking with a mate who is a renault tech I was advised to seal up the gap that the speaker sits in. i did this with a some double sided sticky sealant tape (not sure what the technical term for it is but i was sent some). it looks like black plasticine but very tacky.
the standard speakers are apparently designed to withstand water ingress behind the door card - and the water will drain out of holes in the bottom of the door card. thats it really. i have done that and problem solved
however, if you had aftermarket speakers then they wont necessarily b designed to withsdtand water ingress and you may have issues with the speakers becoming damaged.
i hope that helps?
as with the water ingress in the footwells - from what i remember there was a post about someone stating that it is necessary to check that your drainage holes are clear in the area underneath your front wipers i think?? i dont know as didnt have this myself.
'06 RenaultSport Megane 225: lux, cup pack, full tints, custom exhaust, xenons, xenon white interior and exterior lighting upgrade, tuned, FLI trap 12 active subwoofer (1000 watts)