In a BPM process that starts an Adaptive Case Management Case, I tried to create an XSL based on the Case.xsd that is found in the oramds. I choose the input of the startCase message of the wsdl of the ACM Case.

But I kept running into the following message:
Invalid url: oramds:/soa/shared/casemgmt/Case.xsd
java.lang.IllegalStateException: Invalid url: oramds:/soa/shared/casemgmt/Case.xsd
I tested this in both a WIndows and a Linux (under VirtualBox) installation. Through a question on the BPM Suite - forum, I was confirmed that others hit this as well.

I also saw errors indicating that the 'oracle.home' reference in the adf-config was not found. So I tried to add it as a VMOption in the jdev.conf. But that did not help so far.

Also refering to the a live MDS on a server did not help. When I create a MDS connection to a database in JDev I don't see all the entries I expect from my 11g experiences.

So it seems that the MDS functionality (partly) broke in the 12.1.3 release.
Since I did not found any patches relating the MDS problems I created an SR and got this reply 'The bug have already been raised on which the Development is working and one-Off BackPort has been raised related to this SR.This is fixed in the latest version , we will update you once the patch is ready for this version.'

So we may expect a patch in the near future. If you run in to the same error, you can stop searching. I'll report here as soon as a patch gets available.