For keyswitches I use a separate keyboard - it sends PrCh messages to expression Map (since version 8.5 Cubase able to receive PrCh for change articulations)
And, yes, I can to fix a notes freezing by Plogue Bidule patch (compare data in left and right MIDI monitors on the picture) But why Steinberg not fix it in Cubase?
Also MIDI port routing ability strongly needed in Expression maps - because, for example, in a Play sampler 1 articulation = 1 midi channel. (because factory multypatches with keyswitches not contain all best patches and users needs to add additional patches by hands). For 17-th articulation users needs a second Play on same track. When Expression maps was introduced in Cubase 5, 16 channels and 1 MIDI port output was enough, but since that time many new big sample libraries was created (90 articulations in WARP IV Woodwind, for example http://www.warpivmusic.com/ProWoodwind.html), so for now current state of expression maps function is not useful even for appearance of full list of articulations in Inspector and on a controller lane. Imagine 90 articulations on a controller lane in a current appearance concept - is there any remaining space for a note editing in key-roll editor?