@bbowers132 I don't believe we currently have support for 7z files, but you can customize your config file to include this and it should work. Here's what to do:
Navigate to: C:\Users\YOUR USERNAME\AppData\Roaming\polycade\config
Create a duplicate file of config.default.json
Rename the duplicate to config.json
Add "7z" to the "ext" property of the emulator you are trying to use with 7z roms, like this:
"gameType": "genesis",
"displayGameType": "Genesis",
"enable": true,
"emulator": "RetroArch",
"gameScan": {
"type": "directory",
"dir": "[[gamesPath]]\\genesis",
"ext": ["zip", "bin", "7z"]
},