@rave I contacted @un4saken but seems as though he must be very busy as I've been unable to get a response. So possibly you need to see whether you can work on alternatives such as explained above. As he may not be immediately available to help you.
For loading a screenshot, instead of posting the screenshot as an attachment, you can use an image client like Imgur to upload your screenshot and then post the screenshot as an image in the Forum (instead of an attachment) using the Imgur image URL. @mazl has shown you the steps above how to do it.