Many of the mods by Lewanda and maybe others are on the background map so unless the other adjoining rooms have also been modded they won't fit.

I just downloaded Lewanda's flat screen computer mod but uninstalled it because of this. Then I realised that if I copied the OfficeUpgrade.png only, it worked. I've now got the old-fashioned computer screens in the game still with a level one office, but flat screen computers in the upgraded offices. In a way, this is realistic, as they have old computers at first, then upgrade to newer ones ...

One small problem is that the back of the old CRT screens can still be seen, but I fool myself that it's actually the case of the computer.