I just tried for confirm and downloaded all the latest versions (asset store and website and I don’t see any problems). Hmm.
Can you please open up IGraphAssignableExtensions.cs file and confirm that there is indeed a method inside called “TryReadAndUnbindMappedVariables”? (it is an extension).
Also please try removing previous versions completely and re-import the new versions anew. Maybe for some reason the previous version file is still there and the new one not overwriting it.