If you have two drivers with the same name, you can modify the
* ShortNickName: "HP Color LaserJet Pro M452 my especial printer", on the other, it will be what you see with the name of the driver.
You have to erase all the printers * psprint *, that you have installed.
Verify in the trash that they are really deleted, especially with old versions of the OS. In ARCAOS it is not necessary, it is finally erased.
Rename the folder os2 \ dll \ psprint by psprint-stop or similar. I'm not sure if you have to restart here.
Create a new driver with all the printers or ppd files that you want to include in the new driver. That's why the readme advises you to use different folders to have all ppd files together. As Pete tells you, with a virgin file psprint*no remember de name.zip.
When you install the new printers, a new psprint folder will be created, if all is well you delete the folder renamed to psprint-stop.
saludos