Well, with much trial and error I've fixed it. I managed to position it using "LayoutPos=Bottom ContentAlign=WrapRight" and got it to display the image underneath the contact list by putting the element before the BuddyList one, ending up with this: (for anyone who runs into a similar problem..)
code:
<element content=rcbkd<*PlusSkin Conditions(LargeBG = false) *>(59005)</*PlusSkin*> <*PlusSkin Conditions(LargeBG = true) *> (59004) </*PlusSkin*> LayoutPos=Bottom ContentAlign=WrapRight />
<BuddyList id=atom(abView) Layout=FillLayout() CmdGroup=guid("{16E32D35-5350-4805-B7F0-5E782510AF6F}") />