There's been a bug in SL for several months now, which causes things not to load right or not load at all for some people.
This bug is said to have to do with the Interests Lists, which is basically where SL manages what has priority loading and what doesn't.
The Lindens have been messing with it as they work to implement Server Side Baking, and as a result to that, the priority for loading/rezzing/displaying things is all out of whack. This issue is well-known and documented on Firestorm's JIRA
http://jira.phoenixviewer.com/browse/FIRE-8950This is NOT a viewer problem, it's a SL problem in general. Some viewers seem more susceptible to it due to customizations that in normal situations make them more efficient.
I find that a trick that fixes it for me is to hit
CTRL+SHIFT+R once, that puts you into wireframe mode. Then hit
CTRL+SHIFT+R again to go back to normal, and all problematic objects should be fixed.
There is no word from LL on when this will be fixed. It's been going on for months. We're all hoping once Server Side Baking is implemented, that gets fixed along with it, but this being LL, most likely the entire world will rez gray or some other crap like that.
(doors not seeming to open when you click them is related to this same issue)
