Just a thing I'd like to know for the future

Is it save removing and adding tons of texture packs over and over during the same playthrough?

Do they add any data to my save-game files or are they just added to my game 'on the fly' without touching the save games at all? ^^

And what about Meshes?

Mods like SMIM do seem to have .esp's. Does that mean that they add something to the savegame?

Simple texture/mesh replaces don't really do much to your savegame. Never have.

However, if you have a replacer that comes with a .esp, it does add data to your savegame, so you shouldn't be constantly swapping those. The chance of any problems occuring are low, so a swap or two won't do much aside from give you a warning that your savegame might have an error (it likely won't, so long as the mod only does a replacement). But if you keep doing it, you may introduce errors unrelated to the mod.

It's mods that actively run scripts that are the quaranteed save killers. Texturepacks and other mods without plugins you can add and remove without worries, you should avoid removing pluginned mods, though it's usually safe, but if you remove a scripted mod, start a fresh game.

That's a bit more simple than the full truth, but a good rule of thumb to go by.

See the sticky post on AFK Mods http://afkmods.iguanadons.net/index.php?/forum/332-knowledge-base/ sub forum for everything known so far about "Information Baked into Saves", the first post has been kept up to date