Hopefully got to the bottom of this.... having taken out the glovebox, trim, door cards etc etc.
The plastic behind the door card was intact - so it wasnt that fix.
The water in the footwell must have been coming from above as underneath the carpet was reasonably dry, so it wasnt coming from underneath..
I initially suspected the door seal and removed / refitted several times trying to work out how the seal was leaking. running a hose over the roof/ door line, i noticed the seal seemed to be wetter nearer the front of the sill, and looked like the water was coming from down the door seal (next to dash board) it was around this time i noticed the trim on A pillar was wet! again checked the seal etc and then moved onto the sunroof - checked the drain pipe and this was ok. on removing the front corner of the headlining to make sure the drain pipe was ok, i noticed it was wet there too.
Basically it looks like it was one or a combination of the following;
The sunroof frame design seems to be designed so that if the drainpipe overflows or there is too high a volume for it to drain away quickly enough - it piddles out the top left corner of the frame!
most of the nuts holding the sunroof frame to roof were slightly less than finger tight - these were tightened up.
The drain pipe was removed, blown out and put back on slightly tighter.
the top left of the frame had a wee bit of silicon put on it to fill the "gap" where it overflowed.
The car had also been parked on an incline where the lhs was lower so water would have flowed in that direction and hence the water in the footwell.
After the above was done i parked on the incline and ran a hose over the sunroof and door line for 20 mins - no sign of water on the inside!!!
so hopefully its looking like some progress made and will monitor over the next few days.
hope this helps anyone else with an indoor swimming pool!