I've installed the grid gk5 module and I made a simple layout As I understood reading the module documentation, I should be able to see new module positions when editing/creating a new module, but that isn't the case. What is the problem there, or did I not understand the concept of the module correctly? Also, I'm running Joomla 3, on localhost currently, and the template I use is the News template from Gavick.
I've resolved this issue so I figured I'd post the answer here, it might help someone. The module won't display some more complex modules within itself, more like Random Image module or Custom HTML modules, so that was one issue. In order to show the new positions, you just have to type the name of the module position manually in and it works nicely. I hope this'll be useful.