[cyril_st_john]

One of the great things about Winamp 2 skins in particular is how simple the format is - basically just a bunch of BMPs in a zip file. Pretty much anyone could make one. You didn't need any special software or code knowledge to inspect an existing skin and see how the pieces fit together. You could make one in MSPaint if that's all you had, as I did for my first couple skins.

(There were also a few INI-style config files, mainly to define colors of dynamic things like text. For most skins you would just need to copy the defaults and maybe change a few color hex codes.)

[captbaritone]

Author of the Museum here. Agreed! That was true for "classic" Winamp skins which are what is shown here. I also took a stab at "modern" Winamp skins which were fully dynamic and scriptable and wasn't quite able to bring that to the browser. I did a writeup of that work here: https://jordaneldredge.com/webamp-modern/

[panzi]

Yeah, back in the day I made myself one from screenshots of the in-game GUI of Chrono Trigger. It wasn't very good, but hey, it was mine!