Cunningly used floating point calculations for file size to avoid having to make tough decisions about which integer type to use to do this.
Since the calculation in question is used only to inform the user about file sizes, it is safe to modify it in this way.
Added support for 64-bit compilation
Curtailed precision of floating point output for RAM estimates
Fixed bugs from changes made to label_flats and "labels" matrix definition which prevented code from working.
Added note about bug where progress bar shows negative output at some point