how can i download the update by not deleting and downloading the game again
Hey HeisenbergBlue!
You can download, extract and run the latest update. Saves carry over automatically.
Our Patreon downloads offer a patch system. Where you can update from X version to Y. (Usually 400mb-ish). It will tell you which version of the game you can update from and to. You can only patch the highres game with the highres patch, and compressed game with the compressed patch.
Here's a link to the free version on Patreon:
You will need a Patreon account, but its free to create one if you don't have one already.
Hope this helps!