Ahhh, they're so gorgeous. I love the photos you took. And I always like your models.
If your game is clean (no corrupt CC), uploading sims is pretty straightforward. And I'm sure your game is totally fine. Plus, I want your models. *____*
Sims will show up bald and/or wearing the default short bob hairstyle if you save them with a custom hair that the downloader doesn't have installed. Installing a sim without the custom hair installed used to cause CTD, but after one of the recent patches, crashes pretty much ceased! So you actually don't really have to worry about this anymore - MTS revised guidelines and even allows you to upload sims without stripping the hair, Arisuka mentioned it in a recent upload. People generally still strip the hair (on MTS), but you don't need to. If you've saved the sim with an ND skin, and the downloader doesn't install the skin - they'll show up with pitch black skin, but this also no longer causes crashes. You just have to reselect a skin from the skintone panel and either re-save the sim to the bin/make a change in make-up or hair to "reset" them. So you can upload with your default skin or one of your NDs, it's up to you!
You can upload here with the CC "attached" - just post a list of the sliders/any other content used (to the best of your ability, I know it's hard to track down everything).
For Example: You don't have to list every single specific slider used by Jonha, you can just say that you used his body sliders, etc. Some people include a .rar of the sliders they have installed in their game.
Other requirements for posting are simply that you list any EPs/SPs you have installed that are required (for traits, clothes, etc) and your patch number. Also, include a CAS shot, a profile shot, and one full body shot.
Many creators post both a sims3pack and a .sim file. I personally only download the .sim version.
Some people also include the actual custom content files in the .sim rar/zip file - but different creators allow/don't allow this. If it's something that's old/impossible to find, I usually include it in the zip. You don't have to do this, though, links are totally sufficient.