An "unrecognized" choice adventure is one for which KoLmafia does not provide a way to automate through. That typically happens when KoL adds new choice adventures. KoLmafia throws you into the mini browser when such a choice is seen, where you can handle it by hand.
What is the bug? Contrary to the text of your bug report, the title does NOT "say it all". Apparently, you were automating and encountered the choice adventure which invited you up to Beer Pong and KoLmafia aborted automation and sent you to the mini browser to decide what to do. That sounds correct, to me. What SHOULD it have done, in your opinion?