I may have figured out why folks are having trouble with skins.
I uninstalled the old rainlendar version. The old skins where not deleted from the old installation files.
I installed the new version. To save time unzipping all the skins I liked, I simply copied and pasted them into the Rainlendar2/skins folder.
What I didn't realize, was that when I had uninstalled the old version, it had also deleted the .ini files in each of the skins folders.
Delete all the additional skins (other than the one it came with) from your skins folder, and extract a fresh copy of each skin.
Either refresh Rainlendar2, or restart the computer. Then use the Rainlendar2 "Options"/ "skins" function to switch to the new skin.