Flex 3 as CS4 development tool
Are you as me and using Flex as a development tool and just switched to CS4 development. Well, no problem, you can still use Flex for your coding and debugging.
First you need to download and install Gumbo for flex.
1.) Download Gumbo: http://opensource.adobe.com/wiki/display/flexsdk/Downloads
2.) Place it inside the Flex SDK folder: /Applications/Adobe Flex Builder 3/sdks
3.) Go into the library directory: /Applications/Adobe Flex Builder 3/sdks/{sdk version}/frameworks/libs/
Remove all files except the /player/10/playerglobal.swc.
Before: 
After:
4.) Open the “flex-config.xml” in the /Applications/Adobe Flex Builder 3/sdks/{sdk version}/frameworks/ folder
Replace the text “{targetPlayerMajorVersion}” with “10″.
5.) Open/Restart Flex and add the SDK to flex: Preferences/Flex/Installed Flex SDKs
6.) Create a empty ActionScript Project, In the window make sure to change the SDK (use a specific SDK).
Now you should be able to use Flex Builder as a code editor when building Flash CS4 projects. You can also look on how to develop for CS3. A tip is not to click finish, click the next button and in the field “Main source folder” enter src. Cleaner place for putting the fla & as files.
