@Dazzle101 yes trading directly off the PRT chart is enabled (and I use it). I can't remember how I enabled it, but a quick search through the online help portal suggests the capability is linked to the selection of risk type for your account - it seems if you hold a limited risk account you can't use the dealthru charts capability because you are required to place a guaranteed stop with your order for that type of account.
Hope that helps. If still in doubt, give IG a call locally - whenever I've called them with a question they've always been very helpful.