Ok as for the aileron range, this is as said set by a kidney shaped slot on the bellcrank where the aileron rod attaches to the cables bellcrank, the range should I think off the top of my head plus or minus 1 degree.
As said check the rod for being bent where it comes out of the wing and connects to the aileron......
If all is ok and the range is about right there is the possibility that the aileron has been adjusted on the rods lengths.... this is done if you have an aircraft that is flying slightly out of level, by adjusting the rod end to max range you can lift that wing and make it fly straight and level, so you could have a difference of about 2 degrees from each other......
Put the ailerons in the neutral position, ie controls wheels level across their tops and and check the position of the ailerons against the Flaps, NOT the wing tips...... they should either be level with the trailing edge or both drooping slightly about 1/2 a degree dependant on the year of the aircraft...... if there is a difference, ie one is slightly higher or lower then I would say they have been adjusted to get the aircraft to fly level...... I am taking it on a still day the aircraft does indeed fly level.......
OK now your door. yes this can be as said a worn latch mechanism. this is a megga expensive item BTW.... things to check are is the thing lubed? if not lube the toothed roller and also the doors grooved latch that pokes out, indeed lube the door mechanism as much as you can, they can stick or bind against the door trim so they do not fully extend out.....
next thing to check. on the upper part of the door frame on the front, you will see a little plate with a rolled over lip about 1/2 an inch in size and held on with 2 screws, looking at the fwd edge of the door you will also see a projection that sticks out and when the door shuts it sits behind this lip..... if this is not pulling in the top of the door or indeed sitting close behind it it allows the door to flex and pop open, see if their are witness marks on it where it was screwed on before and whether it has moved. adjustment to that, ie moving it inboard slightly can normally sort this problem out........
ok, off the top of my head, last idea. the door frame has some little pieces of ally that is riveted to it and then to the frame, these sometimes crack and allow the frame to twist slightly..... push the plastic cabin trim in at the back of the door frame slightly and you will see them, just check they have not cracked........... hope that helps,
How are the door hinges BTW? another stupidly priced item, about £300 EACH!!!!!!!!! thats per hinge not two...
