Hi there, currently if an account is created via steam this will not be able to log into our internal forums however we are working on a way to allow this. For the time being we have a very active community on these steam forums and if you experience any issues please raise them here and we will get back to you as soon as possible.

In terms of purchasing items, this is handled through the game client. You can click on the purchase platinum button and you will be directed to your desired payment method.

Hope this helps. Thanks