Detonations broken?

Challenges just don't register most of the time and some are even not implemented yet probably. The weapon challenges do work somehow but other things seem to be bugged, same as DAIMP. My challenge screen says that I have not completed tutorial challenges but I already got a reward for doing it. And I checked, no, it does not look like doing it again, it says zero, nothing. DAIMP was plagued with this type of problems all the time. It mostly worked fine in ME3, so I presume some faulty detection algorithm or bad code that was in DAIMP is just copy pasted.

Apparently, combat detonations is something that you prime and detonate with combat powers. Like concussive shot or frag grenades, but really, don't know. You probably also have to prime with combat powers. It is also possible that cross-class detonations are not counting. So, if you prime with incendiary ammo and detonate with throw, it does not count neither for biotic nor for tech explosions. But TBH, I just don't know.