I know you can already do this - it simply reads it as geometry, but this only works* when the referenced FP uses the mesh as its display. On the scene i'm working on now, this is impractical because it ends up being a few million polygons.
Could it be changed so that if FP is being used as custom geometry, the mesh output is used regardless of the display mode?
* = by works I mean shows in the viewport, it renders just fine.
To give an example, FP1 is a collection of chairs around a desk. FP2 uses this to put the desk/chairs in a room. If FP1's display mode is Point, FP2 doesnt display anything in the viewport but renders ok. If FP1's display mode is mesh, FP2 shows in the viewport, but its very slow because FP1 is about ~2million polys!