Odd behaviour for an IDE, choose File Open from the main file menu or press the file Open button on the toolbar and the IDE shuts down.
Select "Exit" on the File menu to shut down the IDE and it produces the File Open Dialog.
It seems unlikely that this is intentional behaviour or have the programmers gone mad?
Update: It looks like when XE6 is first opened, the buttons behave properly, then reverse when a new vcl application is created.
The machine is Dell latitude Win7 32 bit laptop.
I have installed XE6 on my Win7 64 bit desktop machine and it appears to function correctly.