Thank you both for your replies. It seems that i was indeed confusing BP-Default and BP-Legacy, so sorry about that.
I am developing a child theme for the Genesis framework, so no worries about my theme 🙂
I think what i was trying to get at, was that to make some of the changes i would like, it appears that i have to modify some template files – for instance the search box in groups and members…if i want it to appear in my entry-header i would need to remove it from the template to get it out of entry-content…and then hook it back in to my entry header. I would prefer to do a remove_action to get it out of the template, but it looks like that is not possible…?
So if BP-Legacy is staying, i assume that i only copy the template files i need to change so that updating is easier…yes?