For working with the AS3 code I have my FlexBuilder setup like this :

Top Level Projects

1. AS3-OSCLib (trunk/as3)

No external dependencies, just the flex sdk library stuff.

2. OSCBox (trunk/oscbox)

Which depends on 

• Minimal Components
• GoAsap
• GoBox
• AS3-OSCLib

Dependencies 

Minimal Components

http://code.google.com/p/minimalcomps/

You can use the .swc or checkout the code as a project. I use the source, checked out into a project called MinimalComponents

GoAsap

http://www.goasap.org

Again, I use the source, checked out into a project called goasap.

GoBox

This is the UI project based on go and is part of the 'Go Playground' here :

http://code.google.com/p/goplayground/

The GoBox svn is here :

https://goplayground.googlecode.com/svn/trunk/MartinWoodMitrovski/GoBox

which I have checked out as a project called GoBox in FlexBuilder.

GoBox also depends on GoAsap and MinimalComponents.