Can MyQ Rollershutter item (or something else) be used to stop garage door while opening?

The MyQ garage bindings work great, but I’ve been trying (and failing) to see if I can stop the garage door while it is opening. My garage gets really hot on sunny days and our living room is above it, so I was thinking about using OpenHab to automate opening it a little bit for ventilation when needed.

I can use the Rollershutter item as a switch in my sitemap to open and close the garage with the built-in UP and DOWN commands, but there is also a stop command that the binding doesn’t recognize:

2018-01-16 10:31:40.360 [ome.event.ItemCommandEvent] - Item ‘myq_GarageDoorShutter’ received command STOP
2018-01-16 10:31:40.603 [WARN ] [nhab.binding.myq.internal.MyqBinding] - Unknown command STOP

I also noticed the value of the Rollershutter item is 100 when closed, 0 when open, and (sometimes) 50 when opening/closing, so I tried setting it to various values between 100 and 0 (including 50) and didn’t have any luck.

I haven’t found anything posted about this anywhere, and it may not even be possible. Has anyone tried this and gotten it to work?