Dear Tony
Welcome to Wine.
After all the searches, I still do not have an overall idea of how to
create an control panel applet. From my current understanding, if I put the cpl (dll) file in "~/.wine/drive_c/windows/system32/", wine control will recognize it automatically, right?
When you add a new cpl, the wine build system does this for you.
If so, is there any instructions on how to build a simple applet under wine (even one that does nothing could work for me). I'd really like to try create and build some test applet in order to understand it better.
As always: Read the source. What you try to do (test applet) is how i started with inetcpl.cpl a while ago.
git has a web interface with a history and the first commit for inetcpl.cpl is a minimalistic control applet. ( http://source.winehq.org/git/wine.git/history/HEAD:/dlls/inetcpl.cpl )