Hello! Thanks for your interest; about your questions:
1) Is it possible to change text border? A black border not so cool.
Currently, no, but it should be implemented in the future, as per those two open issues:
- Allow configuring the borders of the window: https://github.com/haroldo-ok/choice4genesis/issues/56
- Allow to configure the cursor for the menu, too: https://github.com/haroldo-ok/choice4genesis/issues/64
2) Is it possible to hide text border when I don't want to use it?
That's already possible with the "font" command: any pixels of the loaded font that happen to use color index 0 will be treated as fully transparent pixels.
3) Is it possible to check gamepad buttons and move some sprites by buttons?
Not currently; it should implement support for sprites in the future, but having the sprites being fully controllable is a bit out of scope for this humble VN engine. Of course, if I ever implement a full RPG engine in the future, it would probably have this feature. As for similar retro engines with this capability:
- One of my own tools, "Bitsy Converter", with the "libCV" option selected, can generate C files from Bitsy scripts, even though, currently, it does not generate Sega Genesis-compatible code: https://haroldo-ok.itch.io/bitsy-converter
- The source code for the Mojon Twins' "Mega Cheril Perils" also includes all the tools that they used for making it, including the map editors, the image converters and so on: https://github.com/mojontwins/Mega_Perils
4) Is it possible to make game loop? To make a sandbox visual novel?
Yes, you can already do that by using the "goto_scene" command to jump to a different scene; you can use to freely go back and forth between different scenes.