I figured this one out. Believe it or not, it had to do with rapid opening and closing of a hidden window I was using for a dynamically sized image buffer. I use this technique in several areas within the script, including a sockread, timer and alias.
Only one caused instability, and that was the alias, which was called by a mouse movement event(within a pic window). Now, mouse movement menu events seem to have priority over many things and are called very rapidly. Somehow, some way, the combination of this event and opening/closing the window made mirc unstable. Go figure.
