This is the last brick needed to be able to import all variants of "Blackboard" files into Moodle now that MDL-34483 is fixed and that MDL-25492 and MDL-34738 are worked on. This issue is about the "Blackboard" plugin in question/format/blackboard wich is currently refactored in MDL-34738.

Recent versions of the Examview software produce .zip files containing .dat files with exactly the same format that the actual "Blackboard" question format and external images in a folders tree.
Re-using the work done on the "Blackboard V6+" format in MDL-25492 it is possible to "enhance the "Blackboard" format plugin so that it accept both .dat and .zip file. If a .dat file is uploaded it is parsed exactly as before so there si no compatibility problem and no functionnality is lost.
But if a .zip file is uploaded the imsmanifest.xml is parsed, the questions are extracted from the .dat files and the external images are imported with the questions.
So the number of questions format plugins available in Moodle will be unchanged, only a new functionality will be added.
At this stage I think all kind of "Blackboard" questions files will be able to be imported in Moodle.
When this will be done the latest improvement will be to combine the "Blackboard" and the "Blackboard V6+" plugins in an unique one to avoid the need to know which file format to use for a given file. This is the final goal.
But IMHO it seems better to first have the 2 parsers working in 2 separate plugins before trying to combine them.