No Man's Sky

did you go back to the corvette workshop in the same space station that you started it from?

I found that if I change stations while there is an incomplete design, it will not follow me to the next station. Once I finished a new design, my old parts ended up in the cache box.

Sounds to me like this buggy update being this buggy update

I’ve built some invalid designs, such as missing cockpits and it saved fine, although that could be because it was a corvette I had finished beforehand

I have not done much with corvettes yet, so I might have misunderstood, but did you switch your ship to the corvette and then try the builder?