Hello,
Regarding the point 6 (1 product out of the wharehouse, but Paypal is displayed):
In your case, PayPal will always be displayed only if the "Shipping1" shipping method is available for your order. if you really don't want Paypal to not be displayed when the "producto without paypal" is on your cart, the solution can be to "block" the shipping method through the "Shipping prices" tab of the "producto without paypal" (by using the "use price per product" option of your shipping method).
The restrictions are working fine on my end, but it's true that it will only display basic option restriction (minimum/maximum price ...)