Hello Tim,
You’re absolutely right. I forgot to add the instructions to copy the Tobii.EyeX.Client.dll to the Plugins-folder. Added those instructions. Thanks!
It sounds like Unity is loading the x86 version of the Tobii.EyeX.Client.dll. Make sure that you copied the x86/x64 versions of the DLLs to the correct location.
The EyeXClientLibraryDeployer.cs script will also only copy the client library to the root if it does not already exist, so try removing the Tobii.EyeX.Client.dll from the root (and the corresponding meta file).
If it’s still not working for you, then contact me again and I will see what I can do.
Best regards
/ Patrik