How many ways are there to set an offset value in a Fanuc control (such as a 210i) besides manually inputting it on the offset screen, or using G10 or Custom Macro?

I do the setup and maintenance work with several Fanuc controlled routers made by a certain machine builder. All of them have an auto tool probing system, but only a couple of our machines have the G10 and Custom Macro options enabled. So how can these other machines without those abilities automatically set their tool and machine coordinate offsets without using those features? (Please don't tell me they can't, because they do.)

So what secret back door are they using to set these values, and might there be a possible way I can take advantage of it for my own purposes.

I know I can do what I want to do with Custom Macro (and that may be the ideal way) but that doesn't help me with the machines that don't have it, and paying Fanuc to enable it, doesn't seem to be in the cards for the foreseeable future (I keep asking the powers that be, but it never goes beyond getting the quote from Fanuc.)