You need to do the following: (please note: use whatever the downloaded file is actually named. I used staroffice52.bin as an example.
You need to be in kde/gnome/etc.
You (usually) need to manually set the permissions to +x (chmod +x yourstaroffice.bin)
I think you need to be root (I'm pretty sure...)
You can also setup StarOffice to install as a miniscule app server. This places the binaries in /opt or /usr/local or similar. Then when a user runs it for the forst time they install just the "Workstation" version (about 3-5MB per user).
to 'run' the installer from the folder you are in, use
You can look through the help splash when the script starts and see how to set it up for multiple users. It's pretty sweet. ('specially if you have roomates!)