Where did you download it from? I don’t see it here:
http://wordpress.org/themes/search.php?q=splendio
I got it off the web, there is multiple sites with it. It was one I used for a blog and wanted to keep it because I have moved the blog to hosting and wanted to keep the same theme.
Officially, these forums only support themes from the repository on this site, so it’s difficult to know what might be wrong with it.
Do you know where, exactly, you downloaded it from?
That looks to be more than two years old – so that might be part of it. I tried installing it on a test site and got an error message as well:
The package could not be installed. The theme is missing the <code>style.css</code> stylesheet.
So there’s obviously something wrong with it – I can only suggest you find a similar theme from here :
http://wordpress.org/themes/
They are all tested and supported here.
