I did fix a bunch of issues with the potential for stuck notes. However I think there is one residual issue which has been hard to track down, where you can get a stuck note when routed through the track. I'll try and fix it if it doesn't turn into a rathole.
It doesn't happen in direct mode.
BTW direct mode was implicitly the only way that X1 worked, although its completely redesigned in X2. Routing through a track uses a completely independent rendering infrastructure because it has to handle hardware MIDI as well. Hence the complexity.