I think the problem is because Artisteer uses javascript to position those things so the lag between when the page first loads the html and when the javascript executes can cause this kind of problem.

I think the experience of it varies by connection speed/page load speed and by which web browser is used, seems less of a problem in Firefox for example.

Unfortunately I don't really have specific suggestions for fixing the problem, it might be solvable by css but it would take trial and error to figure out if it could be fixed or how to fix it. positioning the images ahead of time by css for example could possibly make the javascript load time problem less noticeable or even fixed, but there still can be some lag also between when the html is loaded and when the css is loaded and applied. loading of css should come from the browser cache after the first request so it should load fast but there is still time to apply it to the html. Artisteer outputs a fairly large amount of css. It might help some to move parts of the css that affect those images closer to the top of the style.css file so they are applied sooner in the processing of the css.

I don't really offer support for modifying Artisteer designs outside of Artisteer and I cannot generally provide solutions to overcome the limitations caused by the choices of the Artisteer team in how they implement the css and javascript.