I've read the creator guidelines, and I can't tell if my object is breaking the rules or not, this section is important

Uploads not allowed on MTS

Unmodified EP/SP/Store content: While it is common practice to modify and use bits and pieces of game content to create custom content, extracting content from an expansion, stuff pack, or Store item and uploading it unmodified is not allowed on this site. You are welcome to upload significantly modified versions of expansion, stuff pack, or Store content, but you can't just be ripping it and changing one tiny thing (or nothing) just so people who didn't purchase it can still use it.

I've modified the booking station from GTW and made it a decorative height measuring thing and removed the actual booking station functionality and machine, is it allowed? I've attached pictures of the original one and my modified one.

I'd say that's significantly modified from the original because it's just decorative now, with none of the original's functions. So I don't see why it shouldn't be allowed.

Thanks, but I'll wait until I get plasticbox's approval.

Ideally you could reference the textures to the original object, that would save some redundancy (and also make it GtW-only as a side effect) -- but since the mesh is already very different, I think it would be OK to upload even so, for the reasons already mentioned. (Note I'm not one of the queue moderators, they have the last say in that regard =)