Land Rover Repair: Sunroof doesnt want to close, andthen, potholes

Question
hi..i own a land rover 97 disco tdi.
my sunroof at the back has been having some problem. it got stuck once..n manage to push it all back. Tht was few months ago.
just today,my fren played with it as in he opened it..it works..manage to open n close.bt after the 2nd time..it could go back anymore..
n when we click the close button, some sound comes out..the sound sounds like a motor trying to run n it runs for quite some time. 10seconds or so.
another thing is.. we manage to push it down so tht if it rains,water wont drop in. BUT! whenever i go onto bumps/potholes, the back will jump off a bit too.
not only that..even when im closing my door..the same thing happens.
any ways to solve it without paying to the repair shop.
if possible, fix the whole ting to move. any lubricants or what.
either that,or at least help me solve a way to close fuly the thing wher it wont bounce off wen i go over bumps/potholes.
pls reply soon.. thanks!

Answer
The original sunroofs that Land Rover used in the Disocvery were plagued by problems like you describe.  They have a new mechanism that addresses those issues; it costs about $400.  You take the side panels down from the interior, then lower the headliner.  With that lowered, you unfasten the roof and take it out.  You transfer the sliding glass and other parts on a workbench andthen refit the whole thing.  It's a 4-5 hour job.