I'm so sorry to you had a bad time with LearnToMod. As stated on the FAQ on learntomod.com, the way to cancel your subscription and get a refund (which you can do at any time) is to email email@example.com with your receipt and request a refund. If you buy from this page, you are buying a recurring one year subscription: https://www.learntomod.com/sign-up/
The receipt should have been sent to the email you originally purchased with. Also, a reminder email should have been sent to that same email.
We also offer LearnToMod free to teachers who sign up through a different page on our website and learntomod accounts to people who buy our books (those are not recurring subscriptions), so for that reason, there isn't a universal 'cancel subscription' button as we don't want to alarm teachers and make them think they have subscriptions when they do not. Though if you bought through paypal, there's a page on paypal where you can cancel subscriptions there.
It sounds like you started with the old skills and drills section with the outdated simulator? We recommend using the new vox-l simulator skills and drills section (at the top of the badges page) when getting started. Sorry for the confusion!
If you decide to give learntomod another shot, and can't connect to our server, the easiest thing to do may be to email firstname.lastname@example.org, as all of our technical help is done by email. (Here's how to change to 1.9.2: http://forum.learntomod.com/t/use-minecraft-1-9-2-w-new-ltm-servers-heres-how/3054)