It sounds like your trouble arises because the design-time vector and the runtime text field come into existence in the same frame, so it's a timing issue where they appear and when you can move them.
The easiest thing might be to avoid this problem. One way would be to create an empty movie clip (on the stage, at design time) to be a holder for the text field, layer it wherever you want, and create the text inside of it at runtime. Another solution would be to create either the vector or the text field (or both) in frame 1, but keep it/them invisible until necessary.