If you have previously recommended this thread, you should see a tick / check mark on the recommend button. Click the tick to undo the recommendation (the tick may appear to change to a cross as you do this.) If you added a comment with your recommendation, you will need to delete that from your facebook wall separately.
It would be great to make the listings more personal with your reviews, star ratings etc. If you have a moment could you write a few words please?
And there must be loads more groups that aren't here! It's actually quite hard to track down what's happening in all the church halls and community centres around the city! Please PM me or write your own listing if your favorite group is missing!