@Leo I have tried your suggestion and it works, but not for everything...
I tried using OPENINLEFT and OPENINRIGHT modifiers on the buttons, to have them affect specific side. I assume you meant these, yes?
These buttons work perfectly:
- Go Up:
Go up to %1 - Favorite Locations:
Favorites SHOWICONS USEQUALKEYS NOOPENINTABS NEWTAB OPENINRIGHT - This PC:
Go /mycomputer NEWTAB OPENINRIGHT - Drives:
Go DRIVEBUTTONS=fixed NEWTAB=findexisting OPENINRIGHT - collection:
Go coll://_current NEWTAB=findexisting OPENINRIGHT
The awesome Command: Go-Relative (go to next/prev sibling folder) do not work in a regular toolbar at all:
- Previous Sibling:
GoRelative SIBLING=prev WRAP SKIPHIDDEN OPENINRIGHT - Next Sibling:
GoRelative SIBLING=next WRAP SKIPHIDDEN OPENINRIGHT
I have no idea how would I make Copy and Move buttons work on specific left->right and left<-right. I would love to have these with specific instructions. I have copied or moved files in a "reversed" direction too many times 
- Move:
Copy MOVE QUEUE=Alpha,quiet
The other 2 navigation buttons ignore the OPENINRIGHT intruction, and always control the active side:
- Back:
Go BACK USEQUALKEYS OPENINRIGHT - Forward:
Go FORWARD USEQUALKEYS OPENINRIGHT
Also check this out - the Back button here does not activate (ie: you can go back) until the right side is activated:
The button to reopen a closed tab also ignores the OPENINRIGHT and acts on an active side:
- Reopen:
Go TABUNDOCLOSE OPENINRIGHT
And a visual example
Can all these be solved?
Anyway, having a multi-line file display toolbar would be awesome and easy... 