xDuke 19.7.1 and 19.8 have had rainbow color issues in Windows 7, Windows Vista, and Windows Server 2008 with a palette color problem as well as some other older games which are also effected when viewed at full screen mode.
With Windows XP and Windows 8, I have never seen the color pallete problems for any of the old games using the 8-bit color depths, and those operating systems should be ok.
With xDuke 19.7.1 I had to run it with compatibility mode as 'Windows XP SP2" or it would crash. However it was not needed on v19.8.
These color fixing methods will also work for other old games such as Diablo 2 and Starcraft, to fix the garbled colors when you run the game in Full Screen mode.
Please read this method completely, it does not work just by changing the theme & has so far worked for everyone, but you have to do it everytime,
*IMPORTANT* - I recommend right clicking also on "YANG.EXE" and change the properties so that it can be run as an administrator shown here http://yang-online.com/images/runasadminwin7.jpg.
Or you might have problems launching games on YANG as it will say "not an allowed player".
Also do the same for your main xDuke executable if you have problems in Windows 7/Vista etc.
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