This is thought and written without knowledge of the 2 case links, but should be considered together. (same problems)
text:
Make it possible that the User can place more than 1 row of options (view, general options…) above each other or vertically.
If possible, allow user-generated rows (eg. one with the score history and the load/save buttons)
the title says it all…I do not understand what you are saying or what the links you have included have to do with it. What problems are you addressing? The links do not refer to placing text anywhere. they refer to a proposed legend and a proposed augmentation to the pie menu.
The "problem" is to include more info and/or to the player.
I think now you have targeted only that right-click thing or as additional screen:
" envision this screen as sliding out from or appearing on the side of the window from a low-profile tab (button) that is vertically labeled "Legend", or "Key""
My idea is about more possible actions at the same time.
e.g. you don't see the undo history if you have another tab opened - to change view, load puzzles.
So for example, you move the history up and you have a second tab visible.
Of course, if you can use the right click with your pies for easy access, this is more or less meaningless - thats why I said "same problem".
It's basicly about saving time that comes grom switching the tabs.
title includes reply.
Note mode was created for this express purpose, ie, to allow the user to add notes to his/her puzzle, so it's already present.
For that reason alone, I would not want to include the change in either of my proposals referred by you in the above.
Selection interface features. Done.