This is now reproducible.  To reproduce:

Start workbench estudio with preconditions enabled.
Reset Tools Layout to return to default configuration.
Type Tab to create a new Editor tab.
In Class Name combo box, type INTEGER_32 to put that class in new Editor tab.
Click on Maximize button to maximum zone with two Editor tabs.
Select View/Tools Layout/Save Layout As and save layout under name "Stoat".
Click "X" in Editor tab for INTEGER_32 to close it.
Select View/Tools Layout/Open Layout and open layout "Stoat".
Estudio crashes withi precondition violation.