Hi Velexia,
I found that by restricting the size of cells in the layout tables that it keeps things nice & neat & prevents any "Spillage" - just open up your layout page, then right-click on one of the table cells, choose "Cell" >>"Table Cell Properties" & in the width section put 50% (if you have a 2 column table layout) - do the same for the column next to it & you should find they keep in place better (I find this also makes modules load faster too, believe it or not.... as they no longer have to re-adjust their sizes when loading, & it actually speeds things up just a little.).
I've also done a tutorial for inserting dynamic rotating images into NewsPortal pages which I will list in the "Tips & Tricks" section, if anyone wants to read it.
Regards,
Karen