This probably comes from the fact I mentioned earlier - that a new topic is also a new post so the rule is triggered twice when a new topic is post. In this case, your regular users will get 2 points and exclusive will get 4. Please try if you post just a reply if it will give you 2 points as expected. You can also check the contents of the debug log, I see that you have it enabled.
To get around this, you can exclude Topics from the rule - Add another condition that is "Content is of certain type" and click the NOT button. On the next screen select Forums / Topic (Content Item). This way it should ignore new topics, but give points for the posts...which are also the topics, so you should be set! Haven't tried it in practice, but give it a try. Playing with this app is half the fun.
Now that I think of it, this will probably conflict with the action that is triggered when conditions are not satisfied...I can't think of a way to get around this right now. Maybe in the end you will have to create a different rule for each content type...