I've put together a quick step by step guide for updating CHD Files to v5 in OS X using chdman and the Terminal.

Please note that this is not a batch process. If someone wants to create a batch processing utility/script (or better still, a quick and dirty GUI for chdman), please post it here.

In the meantime, for anyone who might feel a bit intimidated by the use of the Terminal... Here you go -

1) Make a new empty folder (i.e. "CHD Updates")

2) Copy the chdman utility from MAME 0.145u1 or later to the CHD Updates folder (If you don't have chdman available, follow the procedure for compiling MAME, and use the command 'make tools')

3) Open the Terminal Application

4) In Terminal, type 'cd ' (That's the letters c, d, and a space), drag the CHD Updates folder to the terminal window, and press return

5) Move a CHD file (in it's folder) to the CHD Updates folder (Setting the CHD Updates folder view to list makes the following easier)

6) Alter the name of the CHD file you wish to update (I usually place a '-' at the beginning of the file name)

7) Drag chdman to the terminal window, and type 'copy -i ' (copy[space]-i[space])

8) Drag the CHD file (Not the folder) to the Terminal window

9) Type '-o ' (-o[space]  - NOTE that's the letter 'o' NOT the number '0')

10) Drag the CHD file (Not the folder) to the terminal window again

11) Use the left arrow key to move the cursor to the letter before the alteration you made in step 6, and use the delete key to alter the filename to it's original form

12) Press 'Return'

13) Observe the Terminal window. If all went well, chdman will indicate the progress of the operation, and a new CHD file will appear in the CHD file's folder with the proper name

14) When complete, move the original file (The one with the altered name) to the trash

15) (Optional) Color code the folder to indicate the CHD file has been updated

16) Move the folder containing the updated CHD file back into your ROMs directory

17) Repeat steps 5-16 as needed

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