If it turns red, it is in learn mode status. Moving any controler now and it should be linked to this controller (the red disappears).
When the red don't disappear than no midi datas are going into this VI.
So maybe you are operating on a different midichannel in your sequenzer (that sometimes also happened to me)
It can be checked easely, because performing any notes on your keyboard wouldn't reach this VI instance either.
best
Herb