Question about a certain cc item I found and started using. Is there any way to fix this?

So I found this really pretty looking cc where it's basically a bed with shelves and a desk if you wanted to add that. The thing is you have to put it together yourself which I don't mind.

It's just that it's literally not working for me lol. I've got it set up exactly how it looks like in the picture on the cc's Patreon (ignore the odd colouring, I was going to put it together then colour lol), but I ran into a couple of issues and sadly I can't really contact them because I don't have Patreon, let alone I'm not sure how long ago this was posted.

The first problem I found was literally nothing would go together so I had to use a cheat which is fine – I've been trying to figure out how to use that cheat for ages anyway.

But here's the issue lol. It's not centering. Like, the outer layer will go together and that's cool, but the bed will literally not place and at first I was like "oh, it probably just needs to be up again the wall without the shelf, that's okay I guess." Nope, it's now clipping through the wall.

It's not the cc's fault, I'm probably just doing something wrong lol so I was hoping someone had any advice? Crappy photos plus the cc's page/example for a better idea of what's going on lol