I'm trying to connect two instances of Moodle 2.6 through the use of LTI External tool. LTI consumer can launch quiz on the provider. However, grades are not passed to the consumer. I tried everything I found on the other discussions that might be related to the issue. Web services are enabled on both platforms. Consumer is set to accept grades from the tool. I tried to turn on Debugging to Developer, but it doesn't show any error.
Does anyone have idea what else could be the problem.