Support would tell you your addons are the issue, and to do a clean installation of the game to see if it fixes the problem. If that doesn't work, they are then going to tell you your computer is the problem. -.-'
I've had Runes hang open while crashed and blackscreened, to the point where I have to use the computer's task manager to get the game to close itself down. I've learned to keep the TMGR open while playing in case it hangs like that (which it almost always will after it leaks too much memory.) It's irritating, but not much can be done without someone redesigning the look of the game and the way it operates to prevent memory leaks.
Oh trust me I know. That's why I posted that I've tried it with and without addons and even on a different computer. They can tell me its my system all they want but we all know its the client. I usually keep my task mgr open also for the same reason you do. It's funny how they blame our machines when the only thing in common between all of us is the client.
I need to add, the game is most stable when I am in siege. I very rarely if ever crash/dc anything during siege, but as soon as its over, boom crash.