Solution to dissappearing controls... The truth is out there!
Yeah, I found the problem, or rather the solution, so I decided to put it here in case something similar might happen to any other unfortunate souls. I did the project on one computer, and then moved it to another. Both comps had the vbpowerpack extension installed. The problem however, was that the program's references to it had to be reset. To do this is quite easy (this may also apply to other extensions, but I'm using VBPowerpack here) :
1. If the project is open, go to solution explorer (if you can't find it look under "View" > "Solution Explorer")
2. Expand the "References" sub-section.
3. Right-click on VBPowerpack (or the applicable extensionpack-name)
4. Choose the remove option.
5. Right click on references, "Add" , "Browse" and then choose the vbpowerpack.dll file (The location is in the bin-folder of where you unzipped VBPowerpack).
I hope this helps anyone else, since I realised that a lot of the guys at my university struggled with the same problem (unfortunately none of them solved the problem in time... and of course I only found out afterwards)