Hi,

you might know me as Zv45Beta on BA, here's some ROMs that you can check to add support for more devices.

PPC2000 for H3100: https://ftp.zx.net.nz/pub/archive/ftp.compaq.com/pub/softpaq/sp16501-17000/sp16987.exe
WM2003SE for rx3715: https://ftp.zx.net.nz/pub/archive/ftp.compaq.com/pub/softpaq/sp29001-29500/SP29773.exe
WM2003 for h4150: https://ftp.zx.net.nz/pub/archive/ftp.compaq.com/pub/softpaq/sp28001-28500/sp28385.exe
WM5 for rx1950: https://ftp.zx.net.nz/pub/archive/ftp.compaq.com/pub/softpaq/sp31501-32000/sp31892.exe

If you're feeling adventurous, try porting the MPx200 to CERF, this device received all WM versions ever (except for 2003SE) and is 176x220:
https://firmware.center/firmware/Motorola/MPx200%20%28Stinger%29%20%28CMCS%20Beethoven%29/Flash%20Files/BEN-6-0630/BEN-6-0630-012.img.7z
Though this one installs to SD card for WM5 and above, that might complicate things.

I think stripping the first 32 bytes from the image should be enough to get the iPAQs working.