I compiled the SQLite.Interop.dll for 32 and 64 bits and indeed the instructions were not sufficient. I will update the page.
For using litesync with .NET you will need to distribute these additional files with your application:
We use them in the same way as the files available in the System.Data.SQLite site.
You don't need to compile them by yourself. We can supply them for you after you purchase the commercial license.
For now we don't have a version for testing purposes, but you can check the sample apps.
For testing you can use the SQLite shell.
Please ask if you have any question.