default action but not sure why?

So I have a Motorola Droid 1 running stock 2.2 but rooted. I know that with some apps they'll prompt to use a default when doing something (like ADW when pressing the home key the first time after it's installed). Well I'm running Alarm Clock Plus v2. Occasionally, I'll unlock my phone and see "choose a default for this action" and it'll have Alarm Clock or Alarm Clock Plus v2. I'm really not sure how I got it to prompt that as it happens often. If I choose either choice, nothing appears on the screen. I don't have any alarms set for the daytime. Next time I see it appear I'll take a screenshot and attach it. Any thoughts?