First of all,doesn't the user guide make it clear?I guess not since you're asking here,but I find that rather odd.Anyway,I'm not familiar with this software,but since nobody answers I will make a guess.Usually with this kind of software you have to look in the menu's for 'paste','copy&paste' or 'paste game' or something similar to that.If that's not there then look for 'import pgn' or experiment a bit with anything that says 'pgn'.
It ain't much,I know,but it's the best I can do. 🙂