Hi Emil,
Q) if I use licensed assemblies with add reference on my project, do i still have to add reference on Syncfusion.Licensing.dll ? when I download all my assemblies, it is also included.
A) No, you need not add Syncfusion.Licensing assembly as reference if you use licensed assembly. We have provided Syncfusion.Licensing for those who migrated the application with NuGet or evaluation to license for avoid compilation error and assembly not found issue.
Q) if I use nuget, does it happen every time user uses the application? what do you mean by "one time", if I run it myself one time and publish to the app store, validation is done only when i run it or also it is validated every time, each users are running my app?
A) Yes. It will validate everytime when launching of an application for every users. No. One time means that the license key registration is required only once for the entire application instead of validating every control in the application.
Kannan