That is because you have to use dos...

1) goto the Mix program and rename the exacutable to XMIX(its just easier especially if u are using XP)

2) move the xmix program to a directory of your choice. For the example, im going to use c:\westwood\ra2

3)goto start->run and typ in "command" without the "'s and then hit enter...command prompt should show up...it will be a black screen and it should say c:\> or c>

4)type "cd\"
5)type in "cd\westwood\ra2"
6)type "xmix [mix name] [file]" [mixname is the name of the mix file (ex ra2.mix) [file] is the name of the file to extract from the mix file