Express checkout button disapear after changing attribute of product

[motodecal]

I have several problems with paypal module (v3.8.1) on prestashop 1.6.0.5

 

1. when I changed the color of product, paypal button dissapear

 

http://moto-decal.com/r1200gs-adventure/8/r1200gs-beak-sticker.html

 

when you change color display: none apears in div code and button disapear

 

<div style="float: right; margin: 10px 40px 0px 0px; display: none;" id="container_express_checkout">

 

2. on some products button is not visible at all from the beginning 

 

http://moto-decal.com/reflective-helmet/14/reflective-gs-letters.html

 

3. on shoping cart page there is no voucher picture, paypal button, and also X for deleting a product is missing

 

I am also not satisfied with button position but I will try to solve that later

 

Can someone point me in the right direction

 

Thanks in advance

[EnmarcarCamisetasCom]

I've got the same problem...