Instanced static mesh line tracing

Hi,

I have an issue with line tracing: I can’t get any result hit when I trace through instanced static mesh. We have a big open world map. Some things are meshed by hand, other with foliage brush, which has some assets defined it should spawn / create. I am using line tracing to adjust some stuff. So here’s my LineTraceSingleByChannel call:

GetWorld()->LineTraceSingleByChannel(tResult,tStart,tEnd,ECC_WorldStatic,tParams);

and it works great to detect ground level (landscape) and some static meshes placed by hand. But every static mesh instanced by foliage brush doesn’t return any hit. I tried trace by channel, by objects, defined my new channels / objects in settings->collision but nothing helps.

I suppose it’s more of a general problem, than C++ issue.

Any ideas?
Thank you, Bogo