Custom theme doesn't install (when used blog goes white)

Sounds like you have an error in your them. Try turning debug on in your local install.

I turned on the debug on my local install, made all the changes that I was notified of.

Validated the XHTML and CSS of everything, still works on the local install but not the actual site.

D:

Could there be a difference in PHP versions between the two servers? Do you have access to server error logs?

i’m running PHP Version 5.3.1 on my computer and the host of my website is running PHP Version 5.2.12.

I imagine that makes a difference of some sort?

Yes, it does I’m afraid…

=\ is there anything I can do?

You could try googling for any known issues with PHP Version 5.2.12.