All,
I've written a new AC3D plugin to "Flood select" surfaces. This plugin is for AC3D version 6.0.
Find it at:
http://supercoldmilk.com/ac3dplug/selconn.html
This is a Windows plugin. As with all plugins here, all source is available for compilation on other platforms.
See all plugins at:
http://supercoldmilk.com/ac3dplug/index.html
Dennis