Hi,
1. If you're using the user_points custom fields, you can display the value in a little module or to a specific view.
$user = hikashop_loadUser(true);
if($user) {
echo JText::sprintf('USERPOINTS_HAVE_X_POINTS', (int)$user->user_points);
}
2. The point rounding (user points - payment) allows to round the number of points.
If you set "5" for the rounding, the user will be able to use "0, 5, 10, 15, 20, 25, ..." points.
3. The option "give points when using some" should be set on "give on full price" or "give on price with discount".
It depends if you want to give point on the full price or on the discounted price.
4 & 5. I think you have activated the virtual points ; which is a weird option that I dislike but some users asked for it.
Regards,