Last updated: October 2026
These Terms of Service (“Terms”) govern your use of leosterling.net and the products sold on it under the Leo Sterling brand — currently PuzzleKit and its upgrades and licenses — together with any product we add in the future (the “Products”).
Leo Sterling is a brand of DT Labs LLC, a Montana limited liability company (“we”, “us”, “our”). By visiting this site or buying a Product, you agree to these Terms.
1. What we sell
We sell web-based software tools and related digital resources for self-publishers, teachers and creators. PuzzleKit is a browser-based app for creating printable puzzle books. All Products are delivered digitally. Nothing is shipped.
2. How purchases work
Orders are placed and paid through our checkout partner WarriorPlus and its payment processors (such as Stripe). The price, what is included and the license level for each Product are shown on its sales page at the time of purchase. Products are sold for a one-time payment; we do not currently sell subscriptions or recurring plans.
3. Your license
When you buy a Product you receive a non-exclusive, non-transferable license to use it as described on its sales page:
- Standard license: use the Product for your own projects and the books you publish.
- Commercial / PLR or other upgraded licenses: only where purchased, and only within the rights listed on that Product’s sales page.
Unless your license clearly says otherwise, you may not resell, share, sublicense or redistribute the software itself, your login, or the Product files.
4. Content you create
Puzzle books and other materials you produce with our tools belong to you. You are responsible for checking that what you publish meets the rules of the platforms you publish on (for example Amazon KDP or Etsy) and does not infringe anyone else’s rights. Please review everything before you publish it.
5. No earnings promises
Our Products are tools. We do not promise any level of sales, income or results. Your results depend on your own work, your market and many factors outside our control.
6. Acceptable use
You agree not to misuse the Products — for example by attempting to break their security, reverse-engineer them, use them to create unlawful or infringing content, or share access with people who have not purchased.
7. Availability and updates
We work to keep web-based tools online and to improve them over time, but we cannot guarantee uninterrupted service. Features may change as we update a Product.
8. Refunds
Refunds are covered by our Refund Policy.
9. Limitation of liability
To the maximum extent permitted by law, the Products are provided “as is”, and DT Labs LLC is not liable for indirect, incidental or consequential losses. Our total liability for any claim relating to a Product is limited to the amount you paid for that Product.
10. Governing law
These Terms are governed by the laws of the State of Montana, USA.
11. Changes
We may update these Terms from time to time. The date at the top of this page shows when they last changed.
Contact: DT Labs LLC (Leo Sterling) · 1001 S Main St, Ste 600, Kalispell, MT 59901, USA · leo@leosterling.net