This is a generic ZPM3 adaptation for RomWBW.

There are two ways to launch ZPM3.  First, you can run the command
CPMLDR from a CP/M 2.2 or Z-System command line.  Alternatively, you
boot directly into ZPM3 by choosing the ZPM3 disk from the RomWBW
loader prompt.  The ZPM3 disk must be bootable in this case.

You may notice that there is a ZPMLDR application on the hard disk
image.  This application is equivalent to CPMLDR, but it has some
issues with the number of drives that RomWBW supports.  So, as
indicated above, use CPMLDR to launch ZPM3.

I have not found a way to make ZPM3 start up with any drive other
than A: as the system drive.  So, during the load process, the boot
drive and drive A: are "swapped" so that the boot drive is always
drive A:.  Use the ASSIGN command after starting ZPM3 to see how the
drives get mapped.

Per ZPM3 standard, files are distributed across different user areas
depending on their usage.  Normal applications are in user 15.  Help
files in user 10.  Configuration files in user 14.

In addition to the applications provided in the ZPM3 distributio, the
normal CP/M 3 files are included in user area 15.  A few typical ZCPR
utility programs are also included in user area 15:

 - ALIAS
 - ARUNZ
 - ERASE
 - HELPC (named ZHELP)
 - LBREXT
 - SALIAS
 - SETPATH
 - VERRROR
 - VLU
 - ZCNFG
 - ERASE (named ZERASE)
 - ZEX
 - ZFILER
 - ZP
 - SHOW (named ZSHOW)
 - ZXD

It is a bit confusing, but the ZPM3 system file is called CPM3.SYS.
This is the ZPM3 default configuration and I guess it is done this
way to maximize compatibility with CP/M 3.  You will notice that the
startup banner will indicate ZPM3.