sure i'll help
(i also hope to make this more automatic in the future, which it should be possible on repeat donations).
ok, so
when you donated you should have gotten an email with an activation code.
so click on the "Profile and Membership" button at the top of all forum pages.
now in the upper middle of the page next to the count of how many current credits you have (0), will be a link saying "Activate new code".
click that and then paste in the code you got in your email.
that should add the credits to your account
you can also find this link from your donationcredits history page:
https://www.donation...edits;detail=historyjust look under the "how else may we help you list"
let me know if you need more help.
always makes me very happy when people are using their donationcredits to give out to one another