its possible it was made with the bugged version enterbrain messed up with... so erasing a picture that isnt there causes lag.
thats all i can think off the top of my head.
I don't understand what you mean with "erasing a picture which isn't there", care to explain?
Also, since you're talking about RPG Maker, there is something that I have wanted to ask you since I started playing your games.
Could you move the games that you made with RPG Maker VX Ace to RPG Maker MV?
I ask you this because I am used to play games running on RPG Maker MV engine so I can feel how outdated RPG Maker VX Ace is, the gameplay feels much less smooth, the options are much more limited, the graphics and the interface are much less beautiful, the overall feeling is much less enjoyable.
I think your games have potential. So I think it is a shame that they are hindered by an outdated engine when they could be enhanced with a more evolved less limiting engine, don't you think?
I don't know if you play games from other people, so I don't know if you are aware of this, many people who have used VX Ace to make games have since moved their games to MV to benefit its enhancements and the games really benefit from a more enjoyable overall feeling, the gameplay, the graphics, the interface, the options, everything has been enhanced and feels much better in RPG Maker MV.
As a player, I can tell you that I would enjoy your games much more if they were enhancened with MV because, as I said, I am used to play games running on this engine and I feel really hindered when I play a game not updated which lacks the features from RPG Maker MV. :-s
As a creator, wouldn't you like to give some enhancements to your games too?