Also, the files have to have the right name and must be individually zipped disks. If your names are correct, the 1 dir, should look something like this for example:
- 0001_Wizard Warz.zip
- 0002_Commando.zip
- 0003_Cybernoid II - The Revenge.zip
- 0004_Virus.zip
- 0005_Back to the Future Part II.zip
- 0006_Batman - The Movie_Disk1.zip
- 0006_Batman - The Movie_Disk2.zip
- 0007_Time and Magik - The Trilogy.zip
- 0008_Grand Prix Circuit.zip
- 0009_Rolling Ronny - The Errand-Boy.zip
- 0010_Bard's Tale, The - Tales of the Unknown_Disk1.zip
- 0010_Bard's Tale, The - Tales of the Unknown_Disk2.zip
- 0011_Espionage.zip
- 0012_Rainbow Islands.zip
- 0013_Marble Madness.zip
- ...
There are DAT files for clrmame pro and RomCenter to rename and split the files automatically. There are also batch files (included with the DAT), to sort files into and out of the numbered subdirs.
You'll find the DAT files in the @Main directory in the GameBase Amiga File Archive (near the top, names start with "Dat -").