what does it do?? LSHIFT? it's the left shift key... what does it normally do?

the software just makes a distinction between left and right shift keys... LSHIFT and RSHIFT.
there is also LCONTROL/RCONTROL and LALT/RALT ... and various other names for the keys that are presented to you when you hit them in various setup panels (ie: do-not-pass, round-robin, keymaps, etc)