¿Bug in Control app?

Hello, I have a Control app with a Double Select field, when I select the items with one click it works fine, but if I use the button to move all to the right the field closes and appears with nothing in it, the same occurs if I select two or more items.
I think that it’s a bug, because one month ago it worked fine.
Thank you in advance.

Has you some sample project? It’s working for me.