Ok, that's great, then why does this theme say it is made for 2.0.X only? That's exactly the version of the software I have installed.
It does NOT claim to be a 2.1.X only theme.
which version did you download?
there are three to choose from....I'd assume that the Badem.zip is the one that you want for 2.0.x
it doesn't state it's only for 2.0.x
I think you confused the name of the theme (I could see why) but the 2.0 in the name refers to the version of the theme not the version of smf.....
if you look at the download page it states
Compatible With:
2.0.15, 2.1 RC1, 2.1 RC2
it might be helpful if the creator puts a note which download is for which version of smf....
did what Bloc say work for you to reset to default theme?
If not you can try to use the repair settings tool
https://wiki.simplemachines.org/smf/Repair_settings.phponce reset to default, delete the theme and in your admin under configuration go to themes and layout settings, then to theme settings and click on the red x to delete the template from your admin
then download the correct version of the theme for your smf version, then upload and install