If you cant seem to push forward, search for enemies that may have lost your scent just off the screen. The quality will automatically change To suit slower computers, however you can set the quality to stay how how you like in the ingame menu. Also, make note, specials, character changing and Knockbacks can only executed on foot, knockbacks can only be used when the spacebar starts to flash over your characters head, this will happen if your being badly beaten in a short period of time, Have Fun and remember each character and mount has special bonuses and weaknesses.

Read the ingame tutorial.