Udutu is a free content authoring tool (in the same way that Xerte is), with a reasonable feature set. You will need to register with an email address. Hosting with watermarks is free for quickly testing content, but you will need to pay $19+ per month for Udutu to host your material. However, you can download your completed material for hosting on another site or import it into any SCORM LMS/VLE, NILE included. Test scores, or simply participation, can be included in the Grade Centre.
There is a beta version of a Facebook based LMS currently included free (instructors and users have to install a Facebook App and instructors manage students through a group page), but this isn’t particularly easy for students to find after installing it. Permissions for students have to be set manually, which makes it difficult for large groups of students. There are also a number of odd error messages and personal messaging glitches that make this all rather difficult to use, but it does have some promise and could be used to host other SCORM material. This feature would seem unlikely to remain free in the long term, but it may be a useful tool to experiment with learning modules in Facebook.