I don't want to use, or modify any pre-made strategies, can new strategies be made from scratch, is any language supported for doing so, even scripting?
The bots will come with a premade strategy but you can edit the way you prefer and save as a "new strategy" OR you can create a NEW BOT from scratch as well =)
I don't know in which languages it will be available but certainly not all of them. You should ask @flllexa on TG, he's one of the developers and can answer your question about scripting.