I just figured out how to put body shop in full screen! But now every time I start the program the Sim is shown normally for a second before appearing stretched out with a part of the head cut off.
I've already tried switching between window and full screen mode a few times and restarting bodyshop, but the result stays the same, even after using compatibility mode on it. Does anyone know what I'm doing wrong?
Thanks in advance!

If you put Bodyshop in fullscreen, I'd imagine you get the same issues as if you play your game in fullscreen and it isn't set up properly.

Simplest solution is to put it back into windowed mode again.


Long solution is to go through Graphic Rules and all that, to make sure Bodyshop starts in the resolution you want it to. The Bodyshop files are in this folder:
[path to your installed version of M&G or latest released EP/SP] \TSData\Res\CSConfig

In the case of the UC, it would be something like C:\Program Files (x86)\Origin Games\The Sims 2 Ultimate Collection\Fun with Pets\SP9\TSData\Res\CSConfig

You're going to need a tutorial for that method. It's essentially the same way you'd set up the GraphicRules file for your game (in the \TSData\Res\Config folder) but I think maybe Bodyshop works with different resolutions as it may not work very well for widescreen (seems like it was intended to be windowed).