You're not alone. Never used the lock screen on 109 till it was running my own theme and assumed I did something wrong in plazmic.
The positives with the 109 build is it's alot more responsive and more user friendly; the negatives so far are the issues with the lock screen and lack of start up animation in the media app.
You can still unlock the screen for now using the dedicated button on the top, personally I never use the lock option often.