The install folder would be your "functional" folder...

Ok, as lamens as it gets:
1. Backup your EXISTING INSTALL
2. Make sure you BACKED UP.
3. Unzip the Install Archive that you downloaded from ubbcentral.com
4. Delete the /cache_builders/custom/ and includes/ folders from the unzipped folder.
5. Delete the /styles/wrappers.php file.
6. Upload the files to your existing UBB.threads install folder.
7. Make sure your chmods are correct, again I have an article on UBBWiki: Uploading the Software Files that has correct permissions listed.
8. Run the /install/upgrade.php file from your exisitng installs folder, which will be the folder that your current forum is in, that you just uploaded files to.

If you are not comfortable with backing up or upgrading your forums, you should look for someone to do the upgrade for you, I offer upgrade services and UBB.Central offers them as well

I am a Web Development Contractor, I do not work for UBBCentral. I have provided free User to User Support since the beginning of these support forums.
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