You can already stipulate how many rigs you have in a performance. Just leave the ones you don't use blank. Send the appropriate midi messages when you switch to another performance and you should be good. No rule that you have to use all five rigs in a performance
I tried that, doesn't work If I leave a rig slot empty, the corresponding program change will redirect to the slot in the first position of the performance. That's not at all what I want. Since my foot controller has only 3 patches or programs in a bank, if I go to the second bank, the first patch will generate a program change of 4. I'm in my second song (second bank) on my foot controller. In the Kemper, I would still be in the same performance (same song) and initiate rig slot 1. I want to be in the second performance, first slot!