[SOLVED] Broken theme: missing style sheet

I've looked through the handful of threads that deal with this issue but haven't seen a specific fix for my current problem.

I've updated WP to 3.0.1 and began having "auto draft" issues while running ata 3.4.9. I researched and discovered my fix was to update to 3.5.3 and go from there. I downloaded the release, unzipped, uploaded it to my theme directory, yadda yadda but when I go into wp to manage my themes and install 3.5.3 it shows up at the bottom of the page saying "broken theme missing style sheet."

I've retraced my steps several times and have completely lost my patience. Can someone please help me successfully upgrade to 3.5.3?

Thank you in advance.