Download and install the ProntoEdit v4.0.3 software from the file section. This will require that you have a PC with a COM port as the programming is done via RS-232. Here's the link:[Link: files.remotecentral.com]
F1 Help from this editor is really good. Note that this software is old. I can confirm it works on XP and likely Win7 32 bit (have not yet tested this OS).
There is also a ProntoEdit4 v3.4 users's manual here that will get you started:[Link: files.remotecentral.com]
If you don't have a PC with a com port, you can use a USB to 232 emulator. Some are called out in the Pronto FAQ here:[Link: remotecentral.com]
There are quite a few Marantz 7000 series receivers .ccf config files in the Classic Pronto Files Section here. [Link: files.remotecentral.com]
I suspect that those may work for you but you may be missing a few buttons which you can insert buttons onto a page and then learn ir codes from your Marantz remote. Note that the file you download will be a zip. Inside will be a file with extension of '.ccf'. The .ccf file is the one you open in the editor, not the zip.
If, by chance, your OS is configured to 'Hide Extensions for known file types', I suggest you turn this off when working with Pronto stuff.