A few things, first is simply that when we go to rename a ship design we're only able to use numbers and letters, while when we first give it a name in the New Design tab we can use spaces and various characters as well. Further, the game censors apparently are in effect when you try to name a ship even though only we are the only ones who see our the individual design names. Note that the censors are apparently trying to convert the "offending" word into some unknown and thus unacceptable character, despite chat using * which is allowed in a New Design name.
The maximum characters should be the same as the maximum character for the world Battle Cruiser. Apparently it is not and restrict to be lower. I don't like that because I wanted to name it something with Cruiser other than battle cruiser. The Design name max character should be increased at least enough to re type Battle Cruiser with the Space.