I uploaded a new version.
thanks to @raiwa tips, I made some changes.
@domiosc you can turn off the invoice from admin. I will make the t&c optional in the next update.
@yeno I don't know how to use GitHub. but I can use the help for sure.
I added the checkout_confirmation also to the page via Ajax.
this way more of payment modules will work, with one page only. some still might need the 2 page option.
if you use it and it works on your shipping modules and payment modules please let me know,