Yeah it looks really good. It's gonna be slow development though. I think it's a one-man show. So probably expect this to take 1 to 2 years. Just gut feeling, no evidence to back this prediction up .
Open the Steam game install folder (right click the game in Steam, Properties, Local Files, Browse Local Files...). Inside that directory, there will be a folder named 'Rabbit Burn_Data'.
Download the patch file from the link below
Move the downloaded patch file into the 'Rabbit Burn_Data' folder mentioned above, overwriting the existing file if prompted
Since nobody bothered to look into the data structure, here's a full save file for 1.09e. It's not a registry file like previous versions, this is instead some kind of JSON with foreign encoding I haven't seen before. Unzip this archive to the program's root directory, replacing any other present.
Also note that there are difficulty options to make the game easier hidden in the OPTIONS menu. I used those to make the later levels easier to beat, as some of the end-game bosses have absurd requirements.
If you want to play this game as originally intended and you're using my savefile, you'll need to go to the options menu first and change the sliders back to X1.00 each.
I'm so glad there's going to be a sequel to this game. This game is one of my favorites. The upcoming sequel is looking so good but I hope we can see an update soon on the progress. It's been a while since the last update from the link you provided.