I had a similar problem as archeis trying to activate this theme today, except I didn’t get an error message – only a blank screen for both my admin page and my site as soon as it was activated. It was on a brand new WP install, and this is the only theme I’ve experienced this problem with – all others I’ve tried will activate fine.
Like archeis, I was only able to solve it by deleting the theme from my hosting files (but did not figure out how to successfully install the theme). Let me know if there’s any other info I can provide that would be useful in troubleshooting. Thanks!