1. Run Super Mario Bros Remastered.exe
2. If prompted, drag and drop the "Super Mario Bros. (World).nes" rom into the game.
3. User arrow keys and Z key to select Settings > Left/Right keys to select "Resource Packs" > Open Folder
4. This will bring up the "C:\Users\(username)\AppData\Roaming\SMB1R\resource_packs" folder.
5. Drag and drop the "Enemy Gals Resource Pack (Super Mario Bros Remastered)" into the resource packs folder.
6. Refresh list > Select Enemy Gals, press Z key

Done!
You can play any of the games with the included enemy gals.