Question regarding the use of German "StuH 42" Assault Guns

[Rosollia]

Played Scenario 044 - "HG Assault Guns in Sicily"

At the third turn of this scenario the player gets four StuH 42 assault guns with only HE ammo and an indirect fire capability. I am interested to know how common was it to use these guns for indirect fire by the Germans in WW2? I have thought from what limited information I have read, that these assault guns were armed with HE and HEAT ammunition and used to fill in the role of the short barreled 75mm early Stugs. That is they were used for direct fire against MG nests etc. and the HEAT ammo was there to even allow them to engage tanks in an emergency. Also did the StuH 42 have special sights for indirect fire? What about the guns maximum elevation?

Similary the "Brummbaer" (btw. isn't Sturmpanzer IV the same unit?) and Sturmtiger I have heard were used for direct fire rather than indirect. Yet ingame they are also available as SP artillery.

I ques in an improvised situation any tank or gun can be used to indirect fire. Just drive the vehicle in a slope to increase elevation if needed and fire away. I remember even seeing a picture of a T-34 tank possibly conducting indirect fire. Can't talk much about accuracy in those cases I'd imagine.