What extension was it - what does it do? Supplying this information, may get you some more help ;-)
I just checked my config folder and couldn't find anything with that extension.....
The file in question is a compressed file that is often used for files lik patterns (.pat). I've tried extracting .asl files and have had no luck with winzip or vista 64 extraction tools. Once you've figured out how to extract the file, the files should have relevant extensions and they will likely go in a /presets/ folder. Though if you figure out how to extract this file I'd like to know how you did it.