I downloaded the Cobl cosmetic file and transferred the four folders to Data, merging with existing folders . . . but I don't have any more hair, eyes, or race options. What did I do wrong? Do I need to download more than the cosmetic file?

You probably have more than one of the various mods, and I think that causes some trouble. If you have wrye bash, you can fix it. Have to read his documentation for the hows and whys though.

The only other things I have are facial texture mods, which I don't think would cause a problem. Plus, I added Cobl last.

do you have a bashed patch? Might be required for COBL to work correctly.

It sounds like you have the COBL cosmetics resources installed, but not COBL itself. You need the main COBL download- it has the esp files that tell the game to add the hairs etc to the character generation menu.

Just the one thread will do julesmcgee http://www.gamesas.com/index.php?/topic/1118224-best-cosmeticappearance-mods/page__gopid__16433486&#entry16433486

I agree. You did ask about this in your other http://www.gamesas.com/index.php?/topic/1118224-best-cosmeticappearance-mods/, and there are answers there. Let's keep this confined to one topic. Less clutter that way.