Some are, some are not, In North America there are 2 slide mechanism used in TC's, I doubt any of them are used in European campers. There are 2 basic concepts, a toothed gear moving a slotted strip or 2 meshed gears. Usually there will be 2 rails. If so it is very likely you have a slipped a tooth which would account for the twisting. If you can supply photos (esp of the mechanism), I can put you in touch with a manufacturer who may be able to give you a hint on how to rectify the situation. In fact if your register at www.natcoa-forum.com
and post them there, there are 3 or 4 manufacturers who may be able to steer you in the right direction.