i believe that rating system serves a purpose. You use it in order to give to a community your opinion about a product(using the 5 star system ). The fact that it is free does not by any way means that, in case you rate it, you have to give it a 5 stars. If this was true, the first 3 stars would be disabled and only 4 or 5 ratings would be allowed. Why don't you propose this to wordpress.org?
I believe that instead of "punishing" users by writing this kind of responses (i have seen a similar response to someone who also did not like your free product) it would be better to try to help users by telling them something relative to their comments or questions. For instance, in my case you could tell me how to enable sliders since this was my issue (i spend some time creating 3 sliders that were always disabled)
I apologize for not reading everything concerning your free plugin. I think that ease of use is a very important factor in rating a plugin. Finally i managed to enable them by finding a very small bar on the right side of the screen where you choose slider skin... After this, i tried to use 2 skins that look very nice on your screenshots but when i used them writing your shortcode, they occupy a very large portion of screen resulting in the appearance of scrollbars which is something i do not like (i think it was on Vania skin). Tried to find how to specify a size, did not find it (this should be easy) and stopped there.
As i told you some skins for me look very nice and promising (although i can not understand how come and you have decided that this is a great product as you mention), wish your next version will be easier to use (for my standards) and give it a higher rating.