Flash isn't a software development kit. It has many disadvantages over lower level programming languages (like Java and C++). Adobe now does offer Adobe AIR, an extension for Flash (and Flex) which brings your RIAs (Rich Internet Application) to the desktop.
General notice: from now on, I would like to ask everyone to put [AS2] or [AS3] (corresponding to the version of actionscript you are using on your project) in front of their post titles when the question is actionscript related! Please help us help you faster. Thank you.