Common issues
From 360Works Product Documentation Wiki
Webviewer is black or has Red X
this happens b/c Java now requires the same jars for applets as it does for webstart, all 360Works plugins had to be redeployed to comply with this. The solution is to uses latest versions of the all 360Works plugins.
Unsupported class version
This can happen on Leopard if /System/Library/Frameworks/JavaVM.framework/Versions/CurrentJDK is symlinked to 1.6 instead of 1.5 as on most systems. This is a problem b/c Java 6 on Leopard is 64-bit and FileMaker is a 32-bit application. This was fixed in the 360Works plugin framework in May 2011 and likely released with new version of products in June 2011