Edit: Just update all packages before starting the setup, and you are good to go :-D.
Old:
A commit that fixed it was released, but no new ISO files are built yet.
You can fix it command from the terminal - before starting the setup:
zypper in -y patch && cd /usr/share/grommunio-setup && curl -s https://github.com/grommunio/grommunio-setup/commit/4ec354bf84384a06bfea9d0d117041ab76ba45aa.patch | patch -p1 --backup
This installs GNU patch, downloads the patch for the commit and patches the file
Then you can run the setup as usual and it will install everything as selected.