-Fix: nFileSizeHigh is 32-bit

nFileSizeHigh is the high 32-bit, not the high 16-bit.
Should we ignore files > 4 gbyte?
Merge pull request #222 from OlafvdSpek/patch-7

-Fix: nFileSizeLow is 32-bit

ignore nFileSizeHigh which is non zero only for files bigger than 4Gbytes