WW2 Map Co-ordinates and Conversions

OK, this might expose my ignorance of computer programming – but, to hell with it, my ignorances in many other fields have been exposed many, many, times, in the last 70-odd years!!!
A year, or so, ago we were having a great deal of difficulty in mating Lat/Lon with the UK OS NGR system. I emailed OS and asked “How do we do this?”. They replied – basically – that it was TFD and, additionally, there were so many copyrights as to make it very difficult. They gave me the name of a program (Mapinquest) that would convert one to/from t’other. This practically required a 1st Class Honours Degree in Experimental Mathematics (NB I do not have this!) to operate. UK OS NGR has, for example, a false origin. Don’t ask it’s TFD!
Now, look at “Where’s The Path”. (http://wtp2.appspot.com/wheresthepath.htm?l)
Clever piece of programming. But look at the right hand side of the screen (the Google Earth pix bit). You can switch on/off Lat/Lon (both degrees and decimal) and/or UK OS NGR!
It occurs to me that if these guys can do the clever programming to integrate Lat/Lon with UK OS NGR then it must be possible to do the same with all the various map co-ordinates (used by both sides in WW2) such that a “drop down menu” simply asks you which combinations of what Grids, Grid Names, etc, you want in which area of the globe?
Or have I exposed myself again (if you will forgive the coarse connotations)?!!!
Interested in responses.
Peter Davies