Time to give up?
 

Have used fuelly successfully for years, but is increasingly problematic. Just added a BMW Mini One - but apparently this make of car does not exist (even though it is sold in US as well as Europe).

Never mind - just put in generic data - set to UK litres as for previous cars - but hey - insists on gallons, even though all other cars and settings were in litres. Unable to change this.

It is getting too complex to spend time fiddling with it.

In the UK do the Mini's fall under the BMW moniker? Here (and in most places), Mini is it's own Make, and One would be the Model. I see the 2012 Mini One available to choose from.
You can edit your vehicle here: https://www.fuelly.com/driver/cyclist/vehicles/bmw/edit

Also, while you're there switch your Reporting units from Gallons (US) to Litres.

Your reporting units are set on a per-vehicle basis, so it doesn't matter what your other vehicles were set to.

Mini's are a separate brand here in the UK too, with their own dealer network, I've never seen a BMW franchise selling Mini's.

Mini: the FWD BMW