You are able to play Holy Beast Online on any desktop that meets the minimum requirements and has the game installed. If you get the 'Please install the game', 'Install the game first' or anything like that please check if you have installed the Active-X control plugin. The only reason you get that error is because you haven't installed the game or if you haven't installed the Active-X control plugin. Please refer to this page
for installation instructions. If that does not help let me know and I will try to locate the problem more precisely. Normally it should do the trick though .__.