Bringing Dreamcast to date and loving it!

I've installed USB-GDROM, tray and fan upgrade, PicoPSU, purple LED, VGA output to Atlona scaler, and DreamConn wireless controllers. Loving playing my favorite old games (Soul Caliber rocks) after several years. I have 3 questions:

Is it possible via any method to have a controller button combination emulate lid open and close? I've looked to see if any mainstream BIOS has this feature and didn't find it. I'm Considering adding an external switch via modem housing. Might even go as far as 3.5 mm jack that can be closed via home automation relay. From http://3do-renovation.ru/USB-GDROM_Controller.htm what does "When use Button as Lid switch - Put this file to USB" mean. I can see it downloads a file that you can place on USB drive but what Button(s) is being referenced?

Found method to patch CDI images to set flag for VGA. Is there a guide to enable in a GDI?

Didn't use code breaker back in the day. Found a couple versions to download. Can you experts point me to best one for loading on USB-GDROM. I'll gladly pick up a copy on eBay as a backup.