We are in So Cal, so a more cooling oriented environment. The ducts and registers will all be in attic and ceiling. The house has new replaced dual pane / glazed windows and sliding/french doors.

I've done a little research and some people say you should place the supplies along an interior wall, but direct the flow towards the windows/doors, but others have said you should put the supplies over the the wall with the most exposure so it doesn't affect interior temperatures as much. Any thoughts or suggestions?

Also, we will only have 2 returns (one per zone). In the bedroom zone, the option is to have the return in the master bedroom (4br house), or in the main hallway. We tend to close the master bedroom door in the evenings. Is there a recommended place for the return and will we need "passage ducts" (connecting ducts above the door so air can pass from rooms to hallway) for each room? And should the zoning thermostat be located very close to the return?

Thanks again, I really appreciate the help.

This appears to be a replacement system.

Where are return and supply vents now?

Generally, I prefer supply vents to be on outside wall and returns on inside walls.

IMO

This is a replacement system, including new ducts. There are only 2 returns, one located in the bedroom hallways and one in the family room, one for each zone. The supplys have already been placed, some along exterior walls and some along the interior walls. I think the ease of placement unfortunately had lots to do with their placement, but I guess that's not a bad thing if that keeps the ducts from kinking and twisting too much.

I'm thinking about installing the Taramack RAPS in the bedrooms, and especially for the master bedroom suite where we'll have over 400 cfms.