Some sections have size limits....where it's expected that an upload 'should' be small-er.
EG...a 10meg bootskin means you had one heck of a big 'thumbs.db'....
I think most are quite a bit under 10 meg...but you'd have to check with T-Man directly on that one.
There has been issues in the past with oversize uploads...this 'may' be another one of those...