This is a LXQt Windows Classic inspired theme.

For speed, use the Openbox theme of the same name. For accuracy, use KWin with the Aurorae theme.

This is as close as possible without modifying the source code.

If you'd like to improve, or help clean up any remaining issues, e.g. 1 line off, a pixel out of place, additional features, feel free to contribute via Github (check link to Source Code).

Basic Config:

Widget Style
Open LXQt Configuration Center Open the Appearance applet

Click Widget Style if not already active

Set the following:

Qt Style: Windows
Qt Pallette
Window: Red: 212, Green: 208, Blue: 200
Selection: Red: 10, Green: 36, Blue: 106
Visited Link: Red: 128, Green: 0, Blue: 128
Icons Theme
Click Icons Style

Select your preferred Windows XP or 2k/ME icon theme

LXQt Theme
Click LXQt

Select Windows-classic

Font
Set the following:

Font
Font name: Tahoma
Style: Normal
Point size: 8
Cursor
Click Cursor

Select your preferred Windows XP or 2k/ME cursor theme

Click Apply > Close

Additional Instructions and Tweaks can be found at:

https://github.com/pixelocdguy/windows-classic/blob/main/INSTALLATION.md