Hi @stefkeB
All good questions. As always the answers can be found somewhere deeply hidden on the buildingSMART websites 
Most of your assumptions are correct. Just be aware we are talking about the āoldā b-cert certification. It is not possible anymore to start that kind of certification anymore since we have transitioned to a new system.
I assume your questions are about the old b-cert setup, so my answer are also about that.
- The certification is indeed not on a specific version of a product; the certificate says it ācertifies that VENDOR has passed the tests using TOOLā. That is it. Vendors has passed tests and they told the system they did it using a certain tool. Not a specific version, sometimes not even a version that is commercially available for end-users.
- The certification is valid for 5 years
- the most common MVDs (reference/coordination view) are split into 3 kinds of usages. The MVD defines the implementation level (how things are connected and implemented) and on top of that they define a set of classes and properties that are āminimum to execute the use-caseā. For example an MEP softwaretool needs to prove it can export an IfcPump. An architectural tool does not need to prove that. So that is why within the MVD there are 3 sets of requirements that define the minimum definition for the use-case of reference or coordination.
- The old system is indeed time consuming due to a lot of manual checks; and costly
- The tests of the b-cert system were/are indeed secret.
- The ledger of results of the b-cert system can be found here: IFC Certification Participants - buildingSMART Technical This includes the reports and more details
As you know, the new system is going to tackle of of these issues. Of course the new setup comes with new concerns and issues, but we feel those dwarf the benefits.
As you may have heard, it is based on metrics of actual use from the validation service. Some videos I recommend watching are: