Hello! so, for the 8 directional characters, first, you need to use the 8 directional tag on the character, either on the actor in the database, on the comment in the event page the tag should be <8dir> then there is a formatting in the plugins help file, which indicates the order the sprites directions should be placed in
Row 1: Down Left
Row 2: Down
Row 3: Down right
Row 4: Left
Row 5: left
Row 6: Up Left
Row 7: Up
Row 8: Up Right
These is Also now a zip file which includes characters that are setup in the proper format as well :) the height of the characters should not matter as long as they follow this format ^^ If you still need further assistance just let me know and I'll help where I can :D