a few of these people sounds like they have more of a DMing problem to me. Have you ever played the older modules? I mean you can't expect to pick up a module and just run it as is. You have to prep, read it and become FAMILIAR with it. players have a nasty habit of doing the complete opposite of what you want them to do, and you need to be ready for that. I have seen a LOT worse modules than this one. It's all about how you prepare, remember the rules and the story-lines are just guidelines. There are a bunch on here who have added or changed things, that is how you do it, there is no module written to everyone's liking, so change what you want, there is nothing that says you have to have a dragon, if you want to push them, maybe they have family there? maybe they were hired to escort a caravan there, give them a reason to get in there, not just the obvious.