I have managed to upload a ‘logo’ (thumbnail) of the image I want to upload - which is also possible in Gallery but the main image which is less than 5 Mb is ‘not allowed’ as it is a .jpg! First time had this issue. Both logo and gallery image of thumbnail also a .jpg!
OK, So I took another look - this interface is a bit confusing - once I had selected next, I got the familiar interface of drag and drop files etc. Problem resolved.