It was just happening sometimes. Nothing is standing out to me as something specific I was doing before this happened. It felt like it had something to do with the Find Drawing window being open but I have no way to corroborate this. I'll try to keep track of what I'm doing in case the null sprite thing happens again.
OS: Windows 10
Browser: Chrome

     While trying to recreate this I did notice a couple things; deleting a sprite with dialogue doesn't remove the dialogue from the game data. Similarly if you delete a sprite the sprite still exists in the Find Drawing window. Then, if you click on a deleted sprite in the Find Drawing window and then click the duplicate button, the deleted sprite is 'duplicated' instead of the sprite that is actually open in the Sprite window.

Update: also facing this issue sometimes when just making a new sprite

Not sure if this is new to 4.0, but when I duplicate a sprite the sprite appears as a null in the game data. I can place these duplicates in a room but they are not actually interactable, though they will show up when I run the game.

o my bad. I ment "this 2 r gud"

this 1 is gud

I appreciate your enthusiasm for the game, but I have to recommend taking breaks if the game makes you physically ill. I do plan on adding these sorts of graphical options, so if it is too much of an issue you will have to wait until that update.

did you try clicking on the screen? It likes to take focus away from the game at the start, preventing you from looking around

I don't know if I'll be able to get a good map editor going, but I do plan on building out a lot more wallrunning focused platform types. I'll look into more compelling solutions to long falls. Thanks for the feedback!

Thanks for giving it another look! Watching others play my game is always a little nerve wracking but serves as the best blind play-testing. I've just nailed down the bug where you can't move after respawning from a ledge grab. I'm also aware of the diagonal speed increase, and until I figure that out I'm just using it to my advantage for clearing gaps.

Thanks! I haven't gotten around to properly optimizing for different quality levels. I also need to add in options for effects to help performance for those who need it.

Thanks for the interest BlueJackalope. I've just added links in the game description to download straight from Dropbox. Just check the top of the page for the new Direct Dropbox Download Links. Enjoy!

Thanks! Yes, I plan on adding something for that little extra spice. Whether that will be increasing difficulty or narrative or both I haven't decided. I also plan on launching a Kickstarter with the next update around March, so I'll for sure have a plan then.

Thanks for taking a look! Controls are definitely one of the main things I've been working on improving.

Thanks for playing! I made this in 2 days as more of an art project than a game project per se, so there isn't really anything to do other than pick up and throw objects.

This game was made for a design challenge using a strict color palette of 5 colors. I decided to use the challenge to study this art style for use in a future project. I don't plan to expand any more on this 'game', though.

I've posted a new update to the game. This may fix your issue. Can't say for sure since I am unable to replicate it.

What platform are you attempting to play on?

Thanks for the video! A lot of the bugs you've encountered are either taken care of already or I'm working on it currently. As for the wall running, I've bound it to a button, so no more wall running unless you want to. So tighter controls will be coming in the next update.