When working in "Basic Workflow", In addition to the normal blue circle beside a keyframe, I often get orange horizontal pointers next to individual frames, denoting 2 stars or more. I thought these markers were only suppose to occur in the deflicker mode. Can you explain?

The orange keyframes detect changes in Camera Settings (Exposure/ISO/Aperture) and are normally used for the Holy Grail Workflow to compensate for that changes (not deflicker).
They might be created as well if you shoot in A/Av Mode, in that case it's recommended to remove them (Keyframes->Create Keyframes (even spaced).

Thanks, but not clear understanding of (even spaced). Also when I do this, it asks how many do I want to replace? Answer is ?

The idea of keyframes is that you get a couple of frames over the whole sequence, that you want to edit. LRTimelapse will then automatically calculate the inbetween images.
So it's your decision, how many images you want to edit (differently) - if you choose 1 than the whole sequence will have the same settings.
If you choose two - you will be able to edit the first and last - all inbetweens will be lineary connected. If you chose three, you will get a keyframe for the first, the middle and the last image and so on.
So it's your decision.
BTW: did you watch my basic tutorial?
http://lrtimelapse.com/tutorial

About 10 times. Don't remember that being covered.