Thank you, @Banny.
Windows says the file is not read-only, and my changes stayed once I added them to the keyboard section ("X=..."). (And I do keep a back up of the .ini files, in case). Thanks @Blaze (congrats on your 6,700th post!).
Funny thing @Skarn, yes your syntax was a little bit off; but once corrected, it STILL didn't work with the "LShift=" & "RShift=" assignments(?). It DOES work when set to "A=" or "B=", almost. This builds a mine, but doesn't choose the hand/build computer/tool so I can Upgrade the mine:
Selectbuild Mine|Buildit|Setmode 0
I have to play around with it a little more, but I don't know why it won't listen to my Shift key settings. Thanks to you though.