Hello, I'll answer the questions.
1. You can't have the same plugin enabled multiple times due to in RPG Maker, there's only one scene shop, so it won't work when all files modify the same scene. The last file in the plugin list will overwrite everything.
2. Yes, you can adjust that in the code. I left a lot of description lines so people can adjust themselves. Find this line:
// Draw price value with larger font in white
You'll see a line with infoX + 32 -> Increase 32. Basically, find the right description then in drawText/drawIcon, find a word with letter X, then add +number next to it.
Left window is Window_Help.prototype.refresh, right window is Window_ShopBuy.prototype.drawItem. Find those window and adjust anything inside it that has X like I mentioned.
3. I don't use Casper Gaming's ControlsWindow so I don't know 😭. Shouldn't you ask the dev of the plugin? For gamepad keyboard, by default, RPG Maker also support it.
