Correction. I have just rechecked: trying to use the the category filters from my controller works in AL4 but not in AL5.
When using AL5, my Mk1 KeyLab88 correctly displays the instrument name but the knobs to the left of the display, which should scroll through the categories and presets, don't work. The sliders to adjust the parameters work fine.
I don't know whether this is just because my Mk1 controller is no longer fully supported in AL5, or whether this is a global AL5 issue affecting all controllers.