Sell the artwork you create with any pack you purchased.
Edit the textures and files to include them, in part or in whole, in another pack.
You are not allowed to distribute the packs to the public.
You are not allowed to upload the files to any server or allow access to the files on P2P sharing networks.
You are not allowed to modify the items and resell or use them in online games like Second Life etc.
When you're in doubt of what you can do or can't do, just ask us. We'll let you know.
If you have questions, visit our community: Synful Community
Or drop us a line: Contact us