This might seem like a wierd work around, but here's another way to get crosscornerz if you lack the automatic tool:
I assume you have some kind of floor slab.
Copy and paste the floor slab exactly where it lives.
Grab it at a corner and extend it the amount you want the log ends to extend to. It will grow the entire perimeter this amount.
Then select all walls and go around doing an "adjust" to the slab edge - one at a time, but it is quick.
When you are done, delete the extra slab.
Dwight Atkinson