ok, sorry i wasnt so clear i was running on empty after a party
slash is a basic attack where you basically swing like you are swining a hammer. Back is similar to a slash except that you begin the swing with your arm in front of you (think backhanding someone but with a sword). Rise is similar to an uppercut in motion and is used to get under an opponent's guard. thrust is just a stab. other common attacks include cut which is almost entirely useless and lunge which is a very powerful thrust. High, Mid, and Low are the intended parts of the body you are hitting, and are the face, chest, and stomach in that order. for example, slash high would be a swinging blow to the head. Closed and open simply refer to when the sword arm is your front arm or rear arm based on the direction you are headed.
As far as keeping this combo, an aggressive combo (which this is) requires that he be moving forward. if you arent moving your feet, you are defending yourself, which this combo you've chosen is not suited to, though it could be done. Also, since he had no shield, standing still in closed stance is very dangerous because its astoundingly difficult to pary from closed. Anyhoo i tihnk the swings should go into each other without those awkward pauses youve got now between movements, adding followthrough actually will do most of that work for you
Heres an example of how you can make it fluid and move the feet as though he were in real combat:
hope it helps