You add a listing by going to the proper section of the forum such as Zoo tycoon 1 or Zoo Tycoon 2.
Once there you will see that area again broke down into child boards or categories for animals, buildings etc.
The Animals category is again broke down alphabeticaly for easy earch and/or location of a specific animal.
The other sections are also broke down into sub categories or other child boards.
Locate the proper category and open the board for that category.
Now you will see all the topics already entered.
If you are adding a file that is already listed but is by a different designer then in the right category for the file start a new topic. Name the topic the same as the filename of the object, animal etc. Copy and paste another listing and edit it so your needed information is there but the listing format remains the same as the others using copy and paste from the download page on your site. Make sure the link goes to the download page and not the file. We don't hotlink here we just link to the page where people can click a download button to download the file.
If you are adding something that is already available on another site and is listed, there is no need to make a new topic. Just click on the one that is there to open the post. And example of this is Genkicoll's creations where she releases projects at more then 1 site. At the top of the post on the right side you will see a modify button. Use this to edit the post. Look at where the site names appear just under the filename and just add a link to your site's download page for that file. Be sure your new link is done the same as the others.