I suggest an "Edit as text" option for Preferences - Zip & Other Archives - Zip Files - Zip file extensions. This is analogous to the "Edit as text" option in File Types - File Type Groups - Archives. The option makes it easier to add multiple extentions.
I looked for a configuration text file, but all I found was C:\Users\yourname\AppData\Local\GPSoftware\Directory Opus
That doesn't contain what you are looking for.
So what is bothering you ?
Funny, I also have been looking at Preferences - Zip & Other Archives - Zip Files.
Is there something that isn't working with your configuration ?
In meantime "Edit as text" may be added as element of context menu for File Type Group (Archive).
Yes,
But, I think that is only specific to that file.
Perhaps I am wrong ? 
Then edit context for ZIP. In meantime.