Seemingly similar to the issue listed here: http://sourceforge.net/p/spimsimulator/bugs/13/
On my mac (mavericks), I undocked the reg windows, and now no matter what I try, if I redock them they all mix into one window. The reg tabs are no longer seperate from the text/data tabs.
I'm just trying to get it back to the default window layout.
I tried removing the plist file from the Library directory, with no noticable effect.