Not meaning to dig up a several month old thread but this is the only one I've found that had the same issue I had and I figure it may help others out later on who run into the same issue.
Just like what happened to the OP back in June I successfully created a list with all the Shooters using ROMLister. Got it to show up in Maximus Arcade but everytime I tried to play a game that was in my Shooters list it would just give me that beep'ish sound. I figured out why.
I used the Game List Converter that was mentioned in this post by Delusional,
http://forum.arcadecontrols.com/index.php?topic=93864.msg1129116#msg1129116, to open the .lst file I created and take a look at it. I also looked at the original Mame list that Maximus first created. What I found was that I was getting that beeping noice when I tried to select a game because the directory path for my roms was wrong. ROMLister was saving the path for my roms with the path to my ROMLister folder instead. Which is the same folder I saved my Shooters.lst to.
I have attached a quick .txt document showing what I mean.
Not sure if this is something on my end or with ROMLister or what but if anyone knows a fix I would be happy to know.
EDIT: After rereading the attached .txt document I figured I could probably just copy ROMLister over to my roms folder and/or make sure I save my list in the rom folder. That should at least get the path setup correctly. Time to do some more testing.