This shouldn’t be the reason. This is meant to avoid an undeclared variable in case the old title doesn’t have a colon (= no text item 2).
No. This can still be of use for somebody with a similar database GUI.
Starting point is the window as shown in the screenshot.
In the main window (is it called like that?) the order of the displayed columns shouldn’t matter (well, try to have the Title column at the left, since that’s how I tested it). What does matter are the positions of the Title and Original Title fields in the edit window, as shown in the last image here.
PS:
Another (unmentioned) assumption of my script is that the Original Title is empty for all records. (Otherwise it will just get overwritten.)