There seems to be some incorrect information here. There is no such thing as "reflushing the ram" (?) or other initialization - this is probably taken from the UnO manual which has nothing to do with UnO4Kemper.
The UnO4Kemper manual is here , the available key combinations at startup are described here .
The best way to test the FCB1010/Profiler integration is starting up the FCB1010 without cables connected, and check that the display shows "--" and not "00". This way you are sure you have the UnO4Kemper firmware installed.
Next it's easiest to put the Profiler in performance mode and select any performance, not the first one. Then connect both MIDI cables. If the FCB1010 display now shows the current performance number you are sure there is 2-way communication. If not, there is an issue at any point in the MIDI chain. So far I have never heard of any defect or malfunctioning in the Kemper part of the MIDI chain, so if you are 100% certain about both MIDI cables, the issue must be inside the FCB1010 (unfortunately every now and then I notice a report of bad solder joints inside an FCB1010). Most of the time such issue in the MIDI IN part, because the MIDI OUT path is an essential part of the footcontroller and any issue there is noticed right after purchase. This is not the case with the MIDI IN path.
I've just tried this and still no luck, I'm starting to think it must be the pedal board itself so I'm going to have to try it on another board and see if that makes any difference I guess!