First, wow, thank you for making this. I really love small and uncomplicated game engines. I was unable to get my game to preview in  Google Chrome and a few other browsers.  I setup a new room, added a sprite, drew a scribble from the sprite, placed it on stage and then hit the play button. I didn't see anything?  I love the sprite drawing feature, such a great implementation of that! I did find that they way edit windows stack to the right to be very cumbersome. I would tend to just have whatever asset was last clicked fill a dedicated "properties" area on the right. Great job, looking forward to using this more.

Thanks a lot! :) 

Hm I hoped I had fixed that kind of bug in this version.. A combination of hitting the save button and reloading the browser tab might fix it though? I'll look into it some more! 

The stacking to the right is definitely something that is unintuitive to many people, I am considering other solutions at the moment... Though I personally think it's nice once you get used to it and have a convenient way to scroll horizontally (middle mouse button, trackpad,..) 

Thanks Niki!  Not a deal breaker, the side stacking.  Twine does something similar but vertically.  I feel like if the game window was always the right most of and other panels stacked right that could be a nice balance.  But, again, not a huge deal. I'm really looking forward to using this. Keep on the great work.