just an observation … on the rare occasions I have to anything with graphics in Word, I use two paragraph styles: the first one :fig is where I insert the graphic, or the link if I'm feeling reckless, and the second one :figcap is where I add the caption. :fig is set to keep with next. Lists of figures use the ToC mechanism and the :figcap style.
Whether this will help you with the wrapping I can't say – perhaps yes, by separating questions of graphic layout from the use of a caption. On the other hand, it might be completely against your habits … Oh, and I'm assuming (since you mention captions) we're considering standalone graphics each with its own caption.