The latest Windows SDK can be downloaded from our website:
https://pixelink.com/products/software/sdk/
The installer will prompt you for your SDK licence key. If you do not have a licence key, the SDK can be installed for a 30 day free trial.
For more information on the SDK, see Welcome to the Pixelink SDK!
Or the SDK section of our knowledge base: Software Development Kit Information
The latest SDK release notes can be found in Latest Release - Pixelink SDK