Win32k.sys from 2k3sp2 renders windows only with "Windows Classic" color scheme (gradient in titlebar)

Reproduction steps

• undefine the CSR_DBG symbol in https://git.reactos.org/?p=reactos.git;a=blob;f=sdk/include/reactos/subsys/csr/csrsrv.h;hb=0c64ffd3ab82e1980313a9a7cee3ab41595897bf#l13 and build
• install ros and after 3rd stage bootup replace the following files with their 2k3sp2 version: user32.dll, gdi32.dll, winsrv.dll, win32k.sys
• then reboot another time

Expected result
the gradient within a title bar of any application should look exactly like before this replacement, and same as on Windows
0.4.15-dev-2887-g4339ae8_gradient_ok.png

Observed result
the gradient looks wrong on the Frankenstein
Win32k_Frankenstein_wrong_gradient.png

Please ignore all font issues in those screenshot! Do not discuss them in this ticket!