The answer to your question really is not as simple as it may seem and probably not of much interest to most people here, and could be confusing. Since I actually hang out more frequently at the JP1 Yahoo group you will get quicker answers there. Earlier this week I helped someone put together a device upgrade for the 7200. That would save you a lot of time if he were to post it in response to your asking for it.
But as an alternative, I looked through the files over there and under files|devices|audio there is a file created by Rob Crowe, the chief OFA/JP1 guru, for a Marantz 5200 that will probably come close as a starting point. You can upload that file to KM Master, change to your remote model, and upload the device and protocol upgrades with IR.
You really should read JP1 for beginners, the readme files included in KM Master and the FAQ. BTW, you can enter either OBC's or EFC's in KM Master, you choose on the Setup Tab. For most IR protocols, that would be the end of the story. In this case explaining the relationship between OBC and EFC in the RC5 protocol is somewhat unique and would be extensive.
If that works for what you need then great, if not we'll answer the rest of your questions there at the JP1 Yahoo group. BTW, be sure to tell us your OFA remote model number.
