[Add Files] When tabbing into Target Location, set caret to the far right.

[justcla]

When tabbing from the files field to the Target Location field, the caret is placed at the left.

It might be more useful if the caret went to the end, so a user can append to the end of the value.
Alternatively, when tabbing in, select the whole value (with anchor at the end) so a user can type write over the string to replace the value.