Locking items disables timeline selection, is this broken????

[thepedalman]

Hi all,
I've just spend the day working my way through the most excellent user guide and trying out each new skill/feature on my own test project. I'm up to "Working with markers" and I tried to double click on the timeline to select an area b/w markers but it would not select anything. I worked my way back through the Undo feature until I found that if I had any items locked (from a previous excersize), I can not select anything on the time line. Any thoughts on this? Is the locking feature incompatible with the selection feature. Loving the is program by the way :-)