Unexpected behaviour change in 6.5.4

In version 6.5.1, if the database explorer tree has focus, you can move up/down and expand/collapse the treeview with the arrow keys on the keyboard. Version 6.5.4 behaves the same when navigating folders but if you select a server, database or other objects in the tree then the treeview loses focus, making it impossible to expand/collapse and child obects via arrow keys. This causes user interface issues with regards to keyboard navigation alone but causes greater ssues for me. I have an AutoIt script that loads DBVisualiser then navigates the database tree to expand the correct databases for the system I am developing at that moment. Without the treeview retaining focus, it is not possible to run this script any more with this DBVisualiser version. For the time being, I'm simply using 6.5.1 as 6.5.4 has no changes I require.