First, make sure your story and character arcs are complete. Then, focus on polishing the graphics and sound effects. Test the game thoroughly for bugs and glitches.
Renpy Visual Novel is a software framework. It allows developers to create visual novels easily. It has a simple scripting language and provides tools for handling things like character dialogue, scene management, and user choices.
The color change in your Renpy visual novel can be done by finding the appropriate section in the code or settings. Sometimes, there are pre-defined color palettes you can choose from. If not, you might have to manually input the color codes you want.
It's not that straightforward. You need some technical knowledge and specific tools. First, you have to understand the file formats and structures of both the visual novel and VNDS. Then, you might need to do some programming or use conversion software designed for this purpose.
One way is to first break down the elements of the visual novel. Export the story text, character sprites, and backgrounds separately. Then, in Unity, import these assets. Use Unity's UI system to display the text and sprites. For example, you can create canvases for different scenes in the visual novel. For animations, use Unity's animation system to animate the character sprites.
I wouldn't recommend trying to hack visual novels made with Renpy. It's against the law and can cause serious problems. Respect the developers' work and enjoy the games the legal way.