Hello.
I'm sorry but the solutions have not helped me
But, in reality, it is true that great discoveries come by mistake.
I have tried to do everything they have indicated in the forum: triangular, reset xform, etc. etc. and nothing at all.
But, in one of the attempts, I noticed that one of the monitor screens did look like it was playing.
And I thought .... Damn! I've touched something
So I have gone back to 3ds Max and have looked at what difference there was between the screen that looked good and the other adjusted ones.
And the difference was that, by separating the screens from the rest of the logos to work a little better, one of them, the one that looked good, had stayed with the logos and not with the screens.
So what I have done has been to separate screen by screen leaving them as an independent object and, voila, it has worked.
The fault was that I had the screens and the interior logos as a single object. By separating them and leaving them all as independent objects has been when it has been seen well in Trainz.
I have also separated the trunk bars from the rest of the metal, which also looked the other way around, and it has worked too.
So that was the problem.
norfolksouthern37, thanks anyway for trying to help me and give me possible solutions to my problem.
And now, the interior with its screens as they should be.
Best Regards
Manuel