To register tintii, visit www.indii.org/software/tintii/register, click the Buy now button and follow the instructions to pay via PayPal or credit card.
Once payment is received, you will receive a registration code by email. Then, use the Help > Register item on the menu, or the Register button on the toolbar. Alternatively, access the tintii plugin through Photoshop or Paint Shop Pro. In any case you will be prompted to enter the registration code that you have received. Ensure that you are connected to the internet as you do this, and that your firewall software is not blocking tintii from connecting to the internet.
Registering escapes you from the 21 day trial period on Windows and Mac. Optionally, it also allows you to use the software in plugin mode with either Adobe Photoshop (Windows or Mac) or Corel Paint Shop Pro (Windows only) as a host application. This is the preferred way of working with tintii, as other essential photo editing tools, such as brushes, selections, layers and adjustments are readily available to complement those of tintii.
For Mac users, the app version of tintii (but not the plugin version) is also available from the Mac App Store. This is exactly the same as the version available from the tintii website.