SteamCMD

This isn't exactly a problem with Starbound itself, more so a problem with SteamCMD. But I couldn't find a forum to post this on so here we go!
So basically I'll tell you what happened in a simplified format:

I want to install the Avali race mod and Xbawks's character thingy by extension.
I choose not to download it from Steam due to a bug.
I choose to download it using a third party workshop downloader.
The files are downloaded as .RARs.
I try to rename them to.PAKs, makes my game crash.
I...

SteamCMD