There were times when Crystal was even "ported" as Windows visual theme and later as package that swapped resource files: https://archive.org/details/crystal-xp-3.0

Wow what a flashback! I think I used to use this back in the day.

	▲	pndy 7 hours ago \| parent [-]
		I had tons of these "visual styles" and I remember how MS liked to patch themeui.dll and uxtheme.dll often rendering theming broken. There were also attempts at customizing XP booting screen to achieve the perfect "it's not Windows" effect but that could easily render installation unbootable