With this current version, If I create a new ship design with the designer and I try to upgrade my ship to this new design in this new move, the new design will not be displayed.

It appears that the list of designs that a ship can upgrade to is now loaded into a list and this list is not updated by the ship designer.   I suggest that when I new ship design is created, that the list of possible upgrades for a size of ship hull be also updated as it was before.   As it is now, the new ship appears only on the next turn.