If a layout element will not show up in preview mode, does that mean that it will not be printed if I print the layout?

Right now I have a portal that displays the proper data in browse mode but does not show up in preview mode.

Edit: I also have some lookup fields that are showing up as "?" in preview mode, but work correctly in browse mode. I can't test print ATM.

If an element is not viewable in preview mode it will not print. Preview is just as it says. What you see is what you get. Usually when a field has a ? in preview but not in browse is that the contents do not fit into the field. Simply make the field a little bigger.

P.S. Be careful if you plan on printing portals as they only show the number of visible rows in the portal.