Im still fighting a bit with my own Gui Layout (see WiP threat) and im on the phone…
Check the options of Springgridlayout.
Container.addchild(child, row,column)
And use the Fillmode. (None, Last etc).
You may say Container main has 2 child
Subcontainer 1 and subcontainer 2.
They can be in 1 line or one row.
Each of those subcontainers may hold any element you need. E.g. buttons, text, whatever. For the right position you may add “empty” containers to the subcontainers taking the empty space space or you try working with inlets.
Edit:look to that old post Lemur style and attribute question (Container layout)
If you maybe can make a sketch it may help to understand.
I have made a menu that is using the approach above. All sizes are calculated by display size and depending on size of some elements…