Select the title object on the timeline first. If you are not on the Title Editing screen in the Media Pool, switch to it or double-click the title object on the timeline, then turn cancel or check it. Now you will be able to move the title around.
Alternatively, select the title object, go to Size/Position/Rotation, Create effect, and you can use that to reposition your title or keyframe its movements.
For an effect to work, you have to be on the effect screen and the object selected.
After clicking around for ages I've found that you have to have the cursor in the Title editing text window before attempting to select the same title in the monitor window, otherwise a new Title track is created.