Did you re-enable it while the call was in progress? I haven't tried that in the emulator. I hope you didn't because it's set up to re-enable automatically when the call ends. In the update I put new ticker text while calls are in progress that clearly states that it is pausing necessarily because of the phone call.
Alpha 1 didn't have any phone call detector, so it caused you to always see the lockscreen when you were trying to dial things into your call. If found that it would only happen if you let it sleep initially after dialing on the timeout. If you put it up to your ear immediately - as would most people when dialing calls - the prox sensor would capture the screen off event fully such that it would behave as expected going forward. On the converse you would never escape the lockscreen if you allowed that first timeout screen off to happen after dialing. This is probably why version 1 has been rock solid for you.
The complete "stop working" behavior is when the lockscreen gatekeeper blacklists us for breaking the rules. lol. I've done extensive case testing in the emulator with the myLock lite update and I cannot get it to crash or fail. I basically tried hard to make it break the rules with various call start and stop states (examples: receiving a call while the device was asleep, then hanging up from the device while it was awake & the opposite receiving a call while device was awake then making the other party hang up while it was asleep again), and it was rock solid. I'm sure bugs will still turn up but try it out and let me know if it is feeling more reliable.
Thanks to everyone who has downloaded and posted or emailed feedback. You guys are my testers-- because this is open source & we aren't a software company with paid testers, your patience with the bugs is crucial to continued success and improvement.
For me on day to day use I have 2c running in foreground mode and I never experience problems. I am working on complete version 2d update which implements lite mode option, the phone listener fixes, some options for pattern mode users, and a semi-usable wakehome mode.