I've put up a bounty on a question, which got one response (not addressing the question). I'm reluctant to award the full points because it doesn't really answer the question. However I would like to award "something" for bothering to answer at all. Is there a way I can manually award some of the points without agreeing that this is an OK answer?
It will automatically get half of the bounty if it has received 2 upvotes and is the highest rated answer, without any action on your part. See the FAQ: https://gis.stackexchange.com/faq#bounty
If it's not a good answer then it probably shouldn't receive a bounty just for posting. Community voting will generally decide whether it's a good answer or not.