I grabbed a torrent of what (I think) was a bunch of dictionary files off of Demonoid. Kenkyusha and Kojien were included. I also downloaded JEdict for Mac, unrared the dictionary files I downloaded but now I can't figure out how to add these dictionaries to my EPWING reader.

When I go to "install dictionary" it asks me to browse for a file to install. Which file am I looking for here? Is it the Honmon file? I tried that but it didn't work. I tried it with every file inside the folder I downloaded but none worked. Am I overlooking something really simple here?

You're looking for the 2KB file named 'CATALOGS'.

I keep getting the error message "Can not install CATALOGS.sjs dictionary. Unknown dictionary format". But the torrent labelled all these files as Epwing dictionaries, I don't know why they would be in incorrect format. Is there some conversion tool I need? Sorry for all the questions!

Hmmm... afraid I can't offer any help.
In my case I just went 'File >> Add Dict...' in EBWin and browsed to the relevant file. Maybe things are more complicated on a Mac though...