There is no official explanation about why Cursor Mania was shut down as of 2015. Cursor Mania was a product of The Excite Network's MyWay.com online portal, along with other entertainment products. In November 2015, MyWay announced, without explanation, that they decided to shut down the website and its products.
As a part of the shut down, cursormania.com has been taken down. The Google cached version of the last view shows a goodbye message saying that the product has gone into retirement, and they apologize for the inconvenience. Cursor Mania support forums have shut down as well, giving visitors a message saying the support portal is disabled.