Clicking directly on the Pinterest badge to post to pinterest doesn't work. I get the Pinterest interface, then in the final Pin it -- it gives me the 502 error message. This happens with every card I try to share on Pinterest.  
 
I have tried the other Sell this card options and none of them work for pinterest.
 
Does posting on Pinterest with the Share Pinterest button count toward a "sell this card" commission? (When I get it working    )
 
The only way I do it currently is with my Pin It link on my own bookmarks bar. However, if there is a commission earning way to link, I would prefer that.  
 
Thanks!

I'm glad it had been working for you. I have never had it work since it first began.      So I just have been pinning it with my own pin it link. Decided it was time to check into it