I would like to add that I also can't find these in .crs (Cursor set) files.
Extra cursors I can't configure
When I use windows, there are extra cursors I can't configure, for example when using certain programs, it uses different cursors, and I can tell because I use a custom cursor set, yet these new cursors appear like the default ones, just ones I haven't seen before. I can't even find these custom ones in C:\Windows\Cursors.