The issue in ADK 1703 is that you cannot mount a WIM file in MDT/ConfigMgr, due to a signing issue with the WIM Mount Driver when running a system with UEFI and Secure Boot.
Workaround:
Michael Niehaus did found a workaround today, and that is to use the existing WIM mount driver that is already in the system.
https://blogs.technet.microsoft.com/mniehaus/2017/05/16/quick-workaround-for-adk-1703-issue/
/mike
Categories: ADK, Windows 10