According to this blog post [tele] decided to ship the sources even with r.a.d.controls single developer licenses. This is very good news as the source code is a must for serious development and I am one of those single developers.
There is nothing better to understand "how does this thing work" than the source code (if you are short of source code then you should try Reflector, of course). And if you need a really quick fix (warning: this is good only for urgent quick fixes – the propery way would be to fix it through component vendor – otherwise your code will go out of sync) – there you go, just apply it to source code and recompile.
Good move [tele].