Office of Steam Forum for Model & Toy Steam Gas & Hot Air Engines

Your last photo shows a crack right around the rim .
That is not poor packing or shipping damage
That is Mazac disintegrating  ie zinc pest /zinc rot / mazac rot .
A common enough problem with some engine brands
ie David Auld flywheels. And Fleischmann bearing blocks and flywheels .
Not all mazac is created equal .
There would have been signs on the wheels before he  packed it
 Have a close look at your contents ?
Are all the bits there ? ( jigsaw puzzle time )