I think this product is a bad choice because it does not now allow you to just plug it in, point a remote at it, and choose an S-Video input. This is just going to get harder and harder.
You should go back to looking for a remotely controlled S-Video switcher. You now know more questions to ask the seller before buying. Heck, if the person you bought that switch from is reputable, they might admit that they described it as working or complete and take it back. I mean, it is not working because it is far from complete.
Instead of suggesting some time-consuming things to get you to your new goal (which is making this thing work), I'm going to suggest that you go back to your original goal (which is getting an S-Video switcher).
I mean, if you want something that will actually be simpler, I have at least two old Yamaha AV Receivers that have S-Video inputs (but no HDMI), so therefore can be used for S-Video switching. These, as a matter of fact, will do EXACTLY what you want done. You might say they aren't appropriate, but they're more appropriate than a technological wild goose chase.
Look for an S-Video switcher. Failing that, look for an A/V processor or receiver with few features. All such components have input switchers built into them. But don't go any further down this rabbit hole.
A good answer is easier with a clear question giving the make and model of everything. "The biggest problem in communication is the illusion that it has taken place." -- G. “Bernie” Shaw
