i was wondering is there a patch for nt4 so that systray can have 256 colour icons instead of 16 colour icons

http://www.dr-hoiby.com/TrayIconIn256Color/index.php

I know that's for 98/2000, but you could try the manual fix for Windows 2000 with a hex editor. It may work. Just make sure to back up explorer just in case

couldnt find the references mentioned and the others didnt work either

Yeah, dr. hoiby is the way to go but maybe you should contact him via mail since there's no nt4 patch published on that page (i think).