Does any one know how to import the project into Flex builder 3? I can not even import the project (either flexviewer folder or the specific widget folder) into it, so that makes me impossible to run a mxml file correctly. I believe that FB can only open a project that has a project type file, which ends up with .fxpProperties. So I tried to put the widget .mxml file in the src subfolder under a project that FB can open, and try to run it under that project, but there is always error that prevents it from running.
I also wonder how exactly does the Flex builder compile the .mxml to .swf file, since I've never seen it created a .swf file automatically just by running the .mxml file.
Looking forward to your help!