Building ship in 1.1 - can't place casket

[Bullwinkle]

I'm almost ready to build my ship, so I put down the plans first. Want to see how much room it will take up and build a wall around that area first. Problem is, when it comes to caskets, their plans are red and won't allow me to set them down. Gives message saying must be connected to a ship structural beam, head first. Can't figure how to attach them.

I see the interaction area. I keep that clear. Not sure which end is for the head, so I try both ends, and nothing works. I try cancelling the plans for all ship parts and just lay down a structural beam plans in a field and try again. Same problem. Move to a new field, same thing.

There seems to be no way for the game to accept the casket placement. Suggestions please! And yes, I have mods. Maybe 20.

[gussmed]

You can't place casket blueprints until you've actually built a structural beam. They connect to beams that have been built, but not beam blueprints. Presumably to prevent you from placing both and then canceling the beam.

For the record, the head of the casket is the part that connects.