Make sure you upload the correct folder of the theme. If you want to upload from Dashboard you will need to change the php.ini file which is located in installDir/xampp/php/php.ini
The theme folder structured must be with at least these files:
As @KanonidisBasilis said this is not a WP theme and it seems they don’t have a WP version of this theme. If you want a WP theme you can try to ask the author for a refund which can be a little problematic.