With beta 6 on Win 7 64.
This might have been reported already.
Run beta 6 for the first time on brand new empty config folder, load some of my macro files, import my options from V18 - unsupported I know but slick doesn't migrate my macros properly. Main window has several document tabs showing. Drag one out to a second monitor, now set up one tool window on the left hand side, one on the right and edit window in the middle. Right hand side is the defs toolwindow, left hand side is the open tool window with symbols, class and projects sharing the left hand toolwindow. Save the layout as xyz. Close the floating window. Drag another doc tab out, slick gives me a tool window on the left, edit window in the middle, tool window on the right. The tool window on the right should be defs, on its own, but it's the open tool window on its own. In the left hand tool window there's projects visible, sharing with defs, symbols, class.
Along the way, slick also brings up a spurious floating preview tool-window on the left hand monitor which I never asked for. It did this twice.
Now I go back and try to make slick remember the toolwindow layout - defs on the right, open, class, symbols, projects on the left, save the layout again, switch to standard layout, switch back to xyz layout - slick gets it wrong again. It won't remember - defs on the right, others on the left.
Also I never set xyz layout as the default (at least, I don't think I did) so why did I get the xyz layout selected when I dragged out the second doc tab?
The preview window seems to pop up whenever I drag the defs window from the shared group on the left over to the right hand side - or vice versa. I do have "activate preview window from other windows" enabled so it's probably because of that - but defs isn't one of the ones that's supposed to activate it so it shouldn't really be popping up. Later... turning off "activate preview window from other windows" does stop it popping up like this.
Another thing, if I drag a doc tab out, slick remembers the width of the tool windows correctly but not the height and not the width of the edit window in the middle.