Portals don't slide within...
The entire portal object will slide up, but objects within the portal object wont. If the portal row crosses a page boundary, weird printing things happen.
The way most folks handle this is to go to a layout based on the table the portal is based from, and show it in list view. Objects in list view slide...
"weird printing things happen" - yes, I think I had spotted that. If there are no other suggestions then it looks like I'll need to fundamentally change the report layout. My Problem is that I need informatio from the "base" table and two related tables, and using portals was an excellent way of acheiving just that....
Consider keeping one portal, but basing the layout (use list view) on the other portal's table instead of the "base table".
Thanks - I'm playing with layouts now, I'll try that