Hi,
Of course it would have been possible. But it is how our CleanMart was developed. To replace the current addtocart-quantity layout with "simple" layout, you would need some coding changes in the PHP and CSS files. This is a 100% custom modification and unfortunately we don't provide free support or step-by-step instructions for custom coding modifications.
You may purchase premium support:
www.flexiblewebdesign.com/premium-support
and let us take care this modification for you directly on your website though.
Regards.
Support