Zlash

Zlash is a highly efficient software that can serve as a competent ActionScript decompiler/compiler for Flash .swf files up to version 7. With its help, one can easily extract the source code of any ActionScript, save it in a text file, and effortlessly modify it using the included editor or a preferred source code editor.

The software is adept at recompiling the modified code to produce a new, customized .swf file, even without possessing the original .fla project file. This feature saves users from the hassle of searching for the original files before making any changes to the ActionScript code.

Overall, Zlash is a reliable software that can help users efficiently extract, modify and recompile ActionScript code for Flash files, making it an essential tool in any software developer's arsenal.