Two questions about ART rigging

Yes I have two things I con’t find any info on,

  1. Why do the last joints not get included in the skinning? The finger tip joints, the top head joints, the foot ball joint (in toe less rig) ?
    When I run the skinning section these get left out and I don’t understand why?
    EDIT: I realized that the tip joints were added to the skin cluster, they just didn’t get any weights.

  2. What is the best way to paint weights while also have the rig animation controls present? And I want to switch to FK arms so that I can easily move the arms around to test the weightings.
    Haven’t figured out how to do that either.

Anyone have any tips?

Cheers