InDesign publish online not rendering graphics well

Hi, 

I'm working on a brochure and trying to test the publish online. However some of the graphics are not rendering well when exported. And every time I try to export there are different errors. So on one page (in the screenshot attached) I have 2 containers for jpegs (paper textures) with selected corners rounded. However the exported version is showing the sharp corners in white (2 corners on the small container and 1 white strip on the big container with one rounded corner) - and yes I have made sure the containers don't have any background or line colours. I also have a png on the page with mock-ups which rendered ok 3 out of 4 times and in this final version it has some grey lines that shouldn't be there. I should also add that I had another page with a different container with 2 opposite rounded corners and filled with a jpeg, which rendered ok. Does anyone know why this is happening and if I can fix it myself as I needed published today. It seems more like a bug though, since the errors are inconsistent. Thanks.