Calswr uses the Microsoft Windows version system with version numbers of the form 1.0.0.0 (may be written 1.000).
Right mouse clicking calswr.exe or calswrsetup.exe and displaying the version tab will yield the version number.
Picswr .HEX files containing the PIC16F876 code will be labelled Picswr1000.hex etc.
If Calswr.exe is upgraded to version 1.010 and the PIC hex code is unchanged then the PIC hex code will remain at Picswr1000.hex.
However, if the PIC hex code is updated then Calswr.exe version number will be updated even though it is otherwise unchanged.
The built-in facility to look for an internet update on the www.g3vpx.net website reports whether or not you have the latest version. See Internet updates