Try to start preview with ctrl key pressed, if it is still there then you need to delete it, there are more then 1 way to make a background picture, check these;

select page in step 3, goto properties button, see if there is a backgrouund in graphic tab

if on an object, goto step4 click / select object -> style -> use background pulldown.

if in row formats: select page (step4)  , click object, select row formats, see if you can find picture there.

could also be in template: step2 template, select template structure check page contents.

I have the same problem. I reiwd it over and over again, but that doesn't help. Only when I remove the picture and choose a colour, the picture is gone. When I choose a picture, the old picture is there again. I removed all the files from the server and reload the site, the old picture appears again. I've been busy some 2 hours trying and trying, but nothing helps. I think it must be a bug in the program that came with the latest update.

Problem is solved.

Thanks Gerry for the feedback but how?

maybe you can help other users by providing the solution.