Hey there,
What if you used only the 'Package Game Files' option?
Essentially, it encrypts both the image assets and the code. I have the exact same problem as you with the image assets and the code (it gets stuck in an infinite loop). The creator told me that using just 'Package Game Files' without selecting 'encrypt assets' provides enough encryption.
Hmmm, I'll try messing around with that again. I stopped packaging them with halva because of the save file location issues. Also I think that would break my game's "indirect" support of android via joiplay so I'd need to also make an android version.
I did search their other uploads and I guess they made a CLI webp conversion tool that's free. So I'm using that for the conversation to webp and then using stock RMMZ encryption after the webp conversion. Then I'm just using RM Cook Tools for automatic metadata stuff for now.
I think in all it's like 16 steps to make a shipping build xD
I'll probably make a .bat file for most of it...