Attempts to set logo result in "No Image Uploaded.."

I bought Creolio yesterday and am pretty pleased with it so far, but I’ve been unable to set a logo. I went to upload my file (logo.png), everything went as expected, I selected “Use This Image!”, but when the settings saved and the page reloaded, instead of seeing my logo on the site or its thumbnail in the settings panel, the part of the theme-specific settings where the logo is set still read “No image uploaded..”. I’ve tried different formats and file names to no effect, I’ve used Delete Permanently to clear out the logos that were uploaded and try again to no avail.

I’d appreciate any help to get this working…

URL: http://www.dominionobserver.ca