I think the image loading problem is related to the 'Load group files' checkbox, if you leave it unchecked it seems to work fine.
The error message is:
ERROR Image Reader 3:38 Execute failed: Encountered duplicate row ID "/Users/mader/Documents/TCGA_DICOMS/DOI/TCGA-17-Z011/1.3.6.1.4.1.14519.5.2.1.7777.9002.119175415668704314181906368452/1.3.6.1.4.1.14519.5.2.1.7777.9002.147921136202653008422021343284/000000.dcm" at row number 3
The test file is attached as 000000.dcm