Having the same problem I phoned the US Microsoft Helpline: and was advised that while you may download the 30 day trial version, Registering and purchasing the validation key was only possible if you reside in either "Canada or the US": My original copy
bought from `Microsoft Germany is no longer an option..
The US helpline advised that although I had my original Validating Key, they only had payment records of purchases from the American Continent, We in the rest of the world aparently dont exist in regards to `AutoCollage`