Additional information:

- the high CPU load does not occur, when I use (Microsoft) RDP to connect from home to my work PC. The work PC only shows the high CPU load when working 'at the console'. This may be related to GUI settings that are disabled when connecting with RDP (I've to do more research to understand what is going on here)
- attached a cygcheck report (BTW generation took a long time, i.e. 10 minutes or so)
- attached Xwin.0.log 
- attached .Xdefaults
- attached  .XWinrc (a dummy one, where host name have been renamed)
- attached .startwinrc

Reproduction:
1. fresh boot of windows
2. start X-server, by calling: C:\cygwin64\bin\run.exe /usr/bin/bash.exe -l -c /usr/bin/startxwin -- -clipboard -multiwindow -silent-dup-error
3. have a .XWinrc file that contains some menus, like attachment (hostnames have been renamed here to thumb names) 
4. observe the CPU load (as described in previous email)

Note:
If I remove .startwinrc, the default tray menu starts, but at that time, the ~/.Xdefaults file is ignored. Contrary to the settings in .XDefault, an xterm then get a menu and no correct size and scrollbar. This is something else, but just something that I noticed. Using the .startwinrc file as provided also processes the .Xdefaults file as expected.

Kees