Hi Severin,
Your project looks awesome, I hope you get your offset issues sorted without too many problems.
I recently had a similar issue with offsets which I solved in MCX.
I intended to make a CrosshairsPlus style user aircraft from one of my helicopter tower .mdl's to use as a "what you see is what you get" placement tool for the tower.
I should have been able to slew it into position, pause, record the coordinates from Jim Robinson's built-in scenery gauge, and then plug the data into MCX or ADEX to place my tower. Unfortunately, when I placed the tower, in the sim it came out offset from the position of the placement aircraft.
What I eventually figured out was that even though I had my towers, pads etc, zeroed out (centered) in GMax, in the sim as scenery objects they were not centered when placed by the coordinates, a problem which I had never recognized when placing my towers with EZScenery or Instant Scenery2, which apparently compensate for off-center objects by placing them visually instead of by coordinates.
What I finally did was to open the .mdl for the scenery object tower in MCX, then I opened the MCX Transform Object drop-down menu, selected Move Object, clicked Center, clicked Move, clicked Close, and then exported the modified .mdl.
Now, when I place the tower with either MCX or ADEX, it is placed perfectly in the same position as the placement aircraft. It is actually more accurate than Instant Scenery was, probably thanks to properly centering the .mdl in MCX, the flight simmer's Swiss Army Knife. I have since gone through and centered all of my ChopperWorld X scenery objects in MCX, and made a small fleet of pad and tower placement aircraft which are working much better than I had ever anticipated.
And the MCX Convert and Place Object Wizard is really working out well with my "poor man's Instant Scenery". What better way to pick the object to be placed than to open the library.bgl in MCX and have large multi-viewable images of the objects? Amazing!
As always, thank you Arno!
Cheers
Gman
P.S. Arno, do you think you will ever implement an altitude control for the Convert and Place Object Wizard? Sometimes I want to place a pad or tower on top of a building or high-rise which requires placing an object above ground level.