Okay, I understand that you say skinning will not be applied to elements of some programs. That's too bad, but at least it is an answer, and I will turn to other things. The WB program is apparently working as designed. Stardock and its stuff still make my life better -- great value for money there.
With respect to the skinning of SkinStudio, I have spent the past six or so hours downloading everything afresh, uninstalling and reinstalling everything, and testing. I got to the same state more than once -- SkinStudio is stuck on a skin and will not skin.
On the most recent iteration of this, I stopped WindowBlinds (by setting the default theme) before I installed the skin (True Classic.wba) on which SkinStudio seemed to get stuck. Now it is not stuck, and it will skin. On all earlier iterations I had had WindowBlinds up and running and skinning when I clicked on "True Classic.wba", and if I remember correctly this not only installed but also applied the skin (and apparently caused SkinStudio to stick). This time, since WB was not running, clicking the "True Classic.wba" simply did an install. Later, in WB, I selected it, and things seem normal.
So as it stands I will live with progress bars not skinning and will accept it as an unknowable anomaly if SkinStudio get stuck again. Thanks for the interest and help.