It maybe because you dont post enough. Come here everyday and stay active. I'm not an expert on how there forums are set up, but the phrase "inactive" is self explainitory. All you have to do is 5 times better posting then what your doing now. Try to get your posts at a good rate. Dont just spam to get posts. If you read the rules they may help too.
All your posts are relatively short so I cant imagine you get any more than 1.5 for each post. ( some are short enough to be considered spam!)
Then you have 1 point taken each day as well dont forget.