I own an AC-707 Autocolor since many many years, one of the best machines ever built by Durst in my opinion, although at this point in time it has too much electronics and no service, so today I would possibly not buy again such an high-tech machine. But what a terrific enlarger!
It seems you already got the basics of the machine in the meanwhile. You probably already understood that what you called the "remote" is a combined "on switch" and three-colours light sensor probe. You can set the head to "B&W only mode" with a three-throws switch and automate the work a bit by using the sensor as a plain lightmeter, which sometimes helps when changing from one frame to another or from one film to another. In order to use it this way, however, the enlarger should also be equipped with the white diffusing filter, mounted on the same red filter assembly. Should your unit lack it, coincidentally I have a complete spare assembly for sale.
Enjoy your AC-707 Autocolor!