there is an error when i try to install

I just downloaded unity to my mac mini and when i try to install it an error message pops up saying “install failed, the installer could not install some files in ‘/ Applications.’ Contact the software manufacturer for assistance.” any ideas on how to fix this? or am I just screwed?

Have you tried searching on Google?

Try to look at this post : Problems installing on Mac OSX 10.5 (Leopard) - Unity Answers

Try to check write permissions on your mac. Other than that: try to bug report it!