We have the problem that MASON hangs when resizing and/or zooming the display window of our application. Since I saw that someone had the same problem earlier, I decided to test with the original apps in the MASON distribution. For these versions of JREs I managed to hang both the Ant Foraging and Tutorial 4 apps; Linux; JRE 5_0_16, 6_0_5, 6_0_7, 6_0_10 Windows; JRE 6_0_7. The program just hangs completely and can't be shut down by clicking on the MASON-console's or the display window's close buttons. No exceptions shown to the console. So either the demo apps, MASON itself or the JREs are buggy. Any suggestions? Our own application can more easily be made to hang, but doesn't consistently do so on the first attempt. Typically one has to resize/zoom in-out quite a lot. The only difference I can see is that ours takes a longer time to redraw than Ants and Tut4. Regards, Pelle