Hi,
1 - Depending the checkout workflow, the "submit" button can be at elsewhere in your page.
But yes, you can use some CSS in order to hide that button (you have classname on every div, so you can target the button easily).
2 - I find the issue with some javascript. I generated a new package with the fix
4 - Like I wrote in my previous message you need to check your order statuses settings.
Regards,
Jerome - Obsidev.com
HikaMarket & HikaSerial developer / HikaShop core dev team.
Also helping the HikaShop support team when having some time or couldn't sleep.
By the way, do not send me private message, use the "contact us" form instead.