The A-Minor 7 will not be too big of a hurdle for you. Also, I acknowledge that there are a number of different ways to play this chord, and the one we will be learning in this guitar course is just one of many. The same is actually true for the song “Knocking on Heaven’s Door”. This piece was covered so many times by so many different artists and they all pu their own spin to it. So don’t get confused if you see this song somewhere else with different chords – it’s not a matter of right or wrong, there are always multiple ways to approach song with your guitar.