Yeah, its really tedious to have that selection list window keep closing after you select a mesh and then make you have to open it again and again to select additional meshes  - especially since it forces you to have to wait through having to scroll all the way down to pick one from the bottomof the list - sometimes through a list of hundreds. 
If Bryce would simply allow that window to remain open at the point of the last selected mesh without closing until you closed it, that alone would be a major time saver. 

However, I think the complaint about all inclusive "uni-meshes" , and meshes that seem to have connecting lines evaporate before they connect to another mesh - similar to how they do if they go below the groung plane, is valid for this post as well. 

If there are some key combinations to use for such problems, I haven't found them.