Using A2k, heavily use xrefs, sometimes with associative hatching. Associative hatches cause some strange behavior. In some drawings, I open them and get that annoying little message:
"Do you really want to do this? "
And this happens before any action is performed in the drawing whatsoever. If I say no (and the drawing happens to be large), it does its thing which sometimes take forever, updating (I think) the associative hatches. Plus It asks me the same thing for every blessed hatch in the drawing. Sometimes I just have to ctl-alt-del AutoCAD to end the process. It would sit for hours if I let it. It will do this in the same drawing every time I open it unless I go into the base drawing (s) and disassociate all the hatches. Sometimes the behavior will change depending on the view. In other words, If I zoom to a different location, save the drawing and go back in, the behavior will sometimes not repeat.
Whats worse is that, if I answer "yes", It will occasionaly go through the process and copy all the nested xref'd entities involved to layer "0" and place them in the drawing. You can imagine how much fun that is to fix. These types of issues render associative hatches nearly completely useless to me. Does this behavior occur in later versions? I have 2004/2005, but have not really upgraded to either yet. Perhaps its about time eh, but I'm leary of what new weird little buggy things await me in those vers.