Import Products page hangs

Hi I wondered if anyone had come up against this issue after creating and editing the export file, I am attempting to re-upload it.

The file is just over 8mb I choose the file and select the update checkbox to update prices hit proceed and it gets to the column mapping page but that stays blank like its still processing..and just hangs.

Any help would be much appreciated.

Regards

Matt

The page I need help with: [log in to see the link]