Adding on to what was said above, the FH staff do not have the source code, meaning that the game cannot be changed. The creator, KovuLKD, left the game one day and has made it extremely difficult to contact him. So, the popular marking/item/etc packs cannot me installed with the official game download
As for your issue, I'm sure that when clicking on the link to a download, it will take you to Adfly, yes? As the name implies, Adfly is full of ads, meaning that random "download" buttons will appear on the page, most likely including stuff that has nothing to do with FH and that contains viruses. What you really want to watch out for is a yellow arrow that will come in the top right of the page after several seconds. When it says "skip add", click it, and it should take you to the real download c: The real downloads should be of no harm to your computer
