its been reported before and is not a bug just a bad design
steps to fix;
1 press the [esc] key to drop the craft UI
2 right click the blue flames to open a new craft Ui and put a greatsword, dagger or sickel in and press the craft
that will give you the weapon
what actually happens is the craft Ui does NOT auto drop after its used so when the game tells you to just add a weapon its telling you bullshit what you have to do is right click the flames now that they are blue... putting the weapon in the first Ui locks up the game

That works, thank you. Good to know Larian are already aware of it, at least if Larian thought they may have fixed it somewhere after any previous report they will now know its not fixed yet so maybe my report sent in will not be entirely wasted effort.
I will keep a save to go back to for confirming any future fixes.
The more I look around reading this forum the more I get the feeling this game is getting an exceptional amount of testing by the public EA adopters.