Is there a Marketing Cloud playground?  I tried logging from a link in one of the Trailhead modules but my user name and password aren't recognized even after I change the password.  I would like to do some of exercises for Email Studio, Audience Segmentation, etc. but haven't been able to do so.  Thanks!

This unit is being pushed as intermediate even though it is missing critical steps towards making use of the material it is presenting, such as step-by-step information how to successfully push the metadata we create and make use of the permissions we are uploading.

As far as I can tell, I am successfully uploading the Customer_interaction_Big_Object.permissionSet through ForceIDE, as I get no errors after save to server, but then this permission set isn't available for me to assign to anyone when I look in the SFDC setup UI for permission sets.

And then I can't upload the data because the object isn't writable, presumably because I don't have permissions.

Morever, the sample "Apex" script isn't even valid Apex.  For examples:
* There shouldn't be any angle brackets in: <Customer_Interaction__b> bo = new Customer_Interaction__b();
* Strings should use single quotes, not double quotes: bo.Account__c = "001R000000302D3";
* Play_Duration__c was defined as a number, not text (and again, double quotes!): bo.Play_Duration__c = "25";

Doesn't anyone give these articles a test drive before publishing them to people who will rely on them?