Unfortunately, the installer is kind of buggy. (Or was, the last time I used it.)
Then again, what installer isn't? :p
I never had any problems with the installer. Even being indecisive about partitioning doesn’t seem catastrophical.
(The Ubuntu installation that I eventually achieved didn't fare much better, btw. Meanwhile, Manjaro or Arch haven't crashed on me in years.)
Unfortunately, the installer is kind of buggy. (Or was, the last time I used it.)
Then again, what installer isn't? :p