I believe I have a solution for the problems with NXT-G and Flash on OSX Lion using a feature of the Mozilla Gecko rendering engine (used by NXT-G to load the flash player), which looks in application specific locations to load plugins.
In short in addition to system and user plugin folders NXT-G will also look in:
/Applications/LEGO MINDSTORMS NXT/MINDSTORMS NXT.app/Contents/MacOS/plugins
If the supported version of Flash Player (v10.0) is placed in this folder and provided it has a later datetime stamp it will be loaded in preference to those in the other folders. Importantly this means that the most recent and secure version of Flash Player can be used in browsers while only
NXT-G uses the legacy v10.0 version.
Download and run the install package I created to patch NXT-G
1. Uninstall flash player
2. Install flash player from the Lego Mindstorms CD (found in the Parts folder) or download v10.0
The v10.0 version of flash player will now be installed in /Library/Internet Plug-Ins
3. Create the application plugin directory i.e.
$ mkdir /Applications/LEGO\ MINDSTORMS\ NXT/MINDSTORMS\ NXT.app/Contents/MacOS/plugins
forward slashes are important
4. Move plugin files to the new directory i.e.
$ mv /Library/Internet\ Plug-Ins/Flash\ Player.plugin /Library/Internet\ Plug-Ins/flashplayer.xpt /Applications/LEGO\ MINDSTORMS\ NXT/MINDSTORMS\ NXT.app/Contents/MacOS/plugins/
5. Update file datetime stamps to ensure they are later than those in other plugin folders i.e.
$ touch -t 209901010101.01 /Applications/LEGO\ MINDSTORMS\ NXT/MINDSTORMS\ NXT.app/Contents/MacOS/plugins/*
6. Install latest version of Adobe Flash Player
Web browsers, e.g. Safari and Firefox, will use the latest version of Flash Player installed in /Library/Internet Plug-Ins while NXT-G will continue to use v10.0.
I'm not part of FIRST LEGO League, but I found this thread useful in solving the Flash problem and I hope this solution will be useful for yourselves and others who find this thread.