So basically as follows:

* happily running 7.3.4, no issues but get nagged toupgrade to 7.4.0. This doesn't go to well, apparently this release is bad?

* upgrade to 7.4.1 from nightly, this works but now I have no skin. 

* try to upgrade 7.5.0, this also works, but same problem - no skin

The site is visible here:

http://www.bukitlawang.com/

It's supposed to be using the Gravity 2-col skin.

Any idea what has happened/how to fix?