The black button would do something: it would lock the doors. Even when the doors are already locked, it re-locks, beeps, and flashes tail/parking lights. The fob has to be near the door you are trying to lock, so does that work? If so, that rules out the door oscillators and their wiring.
I hope I am correct to assume that the car will start with SKS, in other words the fob does not need to be in the slot to power up.
Each door senses separately. Problem in one door should not affect the other door. Is the problem with both front doors, or just one? Only the front doors can be opened by SKS (as well as the hatch of course). When you opened the hatch, are you sure it was actually locked?
Sometimes turning SKS off, powering up (with fob in slot of course), powering down, then turning SKS back on works.
I looked over the wiring diagram, hoping maybe I'd see a possible common point of failure, such as a loose wiring harness, but didn't find anything that would not also disrupt other components.
Does wireless entry work, especially while standing at either front door? If so, that would rule out the wirless remote receiver, as SKS also uses that to hear the fob's response to the oscillators. But then if there was a problem wtih that, all SKS functions would not work.
Another diagnostic trick would be to look at the transmit indicator on the fob. With all the doors locked, the car would send out a poll to see if the fob is around. You can see the fob light blink every few seconds when it does. The car will only do an unsolicited poll at the doors though, other locations and functions require an action on your part to trigger a poll. Example, pressing the hatch switch will have the car check for a fob in your possession. If it weren't for the dome light lighting up as you approached, even the SKS front door open could wait until you touched the door handle before it would check for the fob.
Another thing I might try is change the customizable settings using the THHT then change them back.