I was having issues with the top menu not displaying as in the demo but with a ordinary looking font style. I was contacted by Beto C who had worked out the problem. So full credit for this fix goes to him, And he get my THANKS for fixing an annoying menu display problem.
Beto CActually, i think i saw a bug on the installation of the theme. Open your rt_grunge_j15-bundle.tar.gz file. Notice that there is a "fonts" folder. Go to your web server and check if there is a "fonts" folder. I believe there is no "fonts" folder uploaded. The fonts folder contains the BEBAS font files that is embeded on the theme. Since there are no such files on the your grunge template folder, substitute files are used.
To sum up, manually upload the "fonts" folder from rt_grunge_j15.tar.gz to the grunge template directory on your web server. If this resolves your issues on the top menu, please notify Sean of Rockettheme so that they can include that on future changes of the template, as well as to help others, resolve that issue.