...I spent a year in the MFA ceramics program at U Minn, but i was doing glass.
The deal with porcelain clays is not that they are difficult to form or cast, but
that they require firing to very high temperatures in order to get the vitrification
that you need to produce translucence. And the higher you fire stuff, the rate
of collapses, cracking, and various other failures increases....so until you get
good at it, you can expect some aggravation.
Like I said, I was a glass guy, not a clay guy.