I repacked my Wrar330.exe, by extracting it, placing my registry file (rarreg.key) and some other accompaniment freeware in it. (Like md5sum checker).

I used Winrar to rar it up as a SFX which starts unextracting silently without questions, and overwrites all.

How can I move the associations to it too? Which registry key do I export?

Thanks.

Read this article:

winRAR 3.30 Silent with Registration and Settings