I have an issue that just started today, where (at least) Bowmakers and Marble Masons' buildings don't appear under my cursor when I try to place them for building. I'm level 18, I have the resources, and the 'Cancel Action' button appears at the top of the window, but, no buildings. Also, my Tavern is now invisible!
One thing I can think of that caused this might be that this morning, I upgraded my nVidia drivers to v 296.10. Maybe that's it? Seems an odd and highly specific kind of glitch, but oh well. I did try restarting, re-logging and clearing my browser cache etc, but to no avail.
Windows 7, Firefox 11.0, nVidia 296.10, Flash 11.2.202.233