You need to provide more info before anyone can provide meaningful help.
What OS are you using?
Give an example of each type of game, the file you're using to start it, and what you have in your config file for that emulator.
There's not a lot of magic to Attract Mode. It only looks for what you tell it to look for, and it only runs what it's found.
I use linux, and I've created a directory with shell scripts for each DOS game I want to start. Then, in my config file, I have to put 'bash' as the program, and then search for files with .sh extension. Works just fine. You can do the same thing on Windows using 'cmd' as your program and ".bat" as your extension.