On Microsoft Windows XP, Vista and Windows 7 LispWorks is themed . That is, it uses the current theme of the desktop.
It is possible to switch this off by calling the function
win32:set-application-themed
with argument
nil
.
win32:set-application-themed
affects only windows that are created after it was called. Normally, it should be called before any window is created, so that all LispWorks windows will have a consistent appearance.
CAPI User Guide (Windows version) - 30 Aug 2011