Quote Originally Posted by Arimel View Post
When I originally designed the plate movements it was (and is) rather random. A source that explains the reasoning for the tectonic plate movements would be greatly appreciated.
It's not random at all. If you start reading about it, you'll notice that a lot of your current map makes little sense. That's why I just wrote that you either leave it or dive deep (taking the risk that you'll loose heart halfway - most people do).

These rules of thumb, by Christopher Scotese, are an easy read to start. You should also have a look at Scotese's videos on youtube.