Are you saying the UI shows a partial, but the shade itself doesn't move?
If I press/hold on the iOS Home app Tile for my testshade, I get the usual dimmer and I can slide that to any value. In my virtual window shade driver I receive multiple setPosition() calls.
Obviously the source to Generic z wave blinds isn't available to me and so I cannot say what the ZWave commands are being sent. I altered my virtual driver to special case setPosition() =0 or =100 and to convert them into close() and open().
"hey siri, set testshades to closed" yields "done" and:
position : 0
switch : off
windowShade : closed
"hey siri, set testshades to open" yields "done" and:
position : 100
switch : on
windowShade : open
"hey siri, set testshades to 60%" yields "ok, I set test shades to 60%" and:
position : 60
switch : on
windowShade : partially open
Now my Virtual Window Shade driver performs perfectly IF all ya care about is the Current States
I think this is all I can contribute to this discussion about shades I don't have. It looks like the iOS Home app to Homebridge to Hubitat flow is 'correct.' However, that may be miles away from what Hubitat's Generic ZWave Shades driver is processing. If, for a crazy example, it processes presetPosition() and ignores setPosition(), your symptoms would match. SmartThings spec seems to suggest presetPosition() is the correct method.