I found it easy to claim mine too. I did it over the 'phone, they worked it all out, told me the date it would go in the Bank, and it goes in four weekly. The chap on the phone was very pleasant too.
I was amazed how much they knew about me though . He asked had I ever worked abroad and I was adamant that i had not. After we said goodbye I remembered I had worked in Ireland when I was 17!! a lifetime ago, and although it IS I never think of Ireland as being "Abroad". I called them back in a tizzy thinking I would be in trouble or something for not declaring it, but he was lovely, he said not at all it is just to see if you are owed any pension from that Country :-)
I wasn't, by the way, wasn't there long enough.