Is there a a way out of this?

I had just created the last button (in footer of a list layout), when I went to move it, I discovered clicking on it showed 'item active' on another object and, from then on, nothing else would activate and the activated item would not deactivate. The same object activates whatever I click on. When I deleted the activated object and re-clicked on any item, another object became the only one that would activate. I have tried quit/restart, save as reducing size, export/clone/import, recover db and duplicate layout. The only change I have achieved is that clicking on one particular object activates a non-existent item of the same size adjacent to it - if I try to delete the activated invisible item, it takes the item I clicked on with it. Clicking on any other object the original problem remains.

I just carried out the deletion of the activated invisible item (mentioned in the last line of my post) and it took the button adjacent to it (as described) but, this time, it left another invisible activated object where the button had been, so I deleted that and, hey presto, everything is back to normal.