
I've tried to create a solution myself and initially seemed to have found it by adding the following to the .ini file:
OpenFilePath=thebat.exe,G:\Personal\The Bat\MAIL
OpenKeyPath=thebat.exe,HKEY_CURRENT_USER\Software\RIT
(I got TheBat setup in D:\The Bat!\thebat.exe while the email files of the different email accounts -all from a single user- are in G:\Personal\The Bat\MAIL)
However, I keep getting errors with The Bat closing down.
A 30-day trial copy can be downloaded at: http://www.ritlabs.com/en/products/thebat/download.php