This is pretty easy, it's an annoyance for sure, but I will tell you how.
Make a post with a bunch of submissions - post it, then edit it and you'll see something like (url unfurl="true") (in brackets) with the rest of your link in it. Basically copy this all to Notepad and do Replace from the Edit menu or wherever, then type find "true" and replace "false", then click replace all. Copy your block of text and replace your post with it, and click submit. If you did it right, you will just see text links, not the weird HWBOT previews.
The competition is over but if you ever need to post a lot of HWBOT links in the future, that is how I got just text links. Hope it was understandable. It's quite the annoyance, the forums I came from allowed you to pick if you wanted a preview of things or just text.
