Hey all! I haven't posted here in a very long time, so I doubt anyone even remembers me. That's just fine for me. I just recently got my 5th edition handbook, and looking over it I've spent up a good portion of the night actually hashing out some of the basic rules for Ravenloft. So much about 5th edition I love and funnily so many common sense rules in it that I keep going why didn't 2nd evolve into this first? But that's my personal feeling and of course not the topic of this debate.
Anyways, this is about the homebrewed rules changes that I have created for Ravenloft to work in 5th edition. This, of course, is not everything such as spells and magic weapons, and I am actually considering creating specialty backgrounds for the Land of Mists as well as incorporating the classes such as Avenger, Acolyte and so forth as paths for specific classes wtihin the setting. Some of the information found is of course taken from the 3.5 edition of the Ravenloft book created by White Wolf. I felt that they had some good ideas, and as such I still use them, but instead have changed them to the 5th edition rules.
Anyways, what follows are some basic rules, races and class changes that I am interpretting for Ravenloft. Feel free to use them. I will try to update Domain Lords, add in Backgrounds and the special Ravenloft classes as paths for classes in the game at a later date.
Ravenloft 5th Edition House Rules
Nice! I haven't had a change to sit down and really go over this, but it's great to see someone putting the effort into converting Ravenloft to 5e.
It looks pretty good skimming over it though there are two abilities I think could use some work.
Cutting Words - I don't think that this is worth a power check based on the target. It isn't magic, after all, it's choosing the right words to distract the target from what they're doing. It doesn't have to be vicious and hurtful, just enough to distract or confuse them. I think that this is an ability where the way you use it and why you use it should decide whether it causes a powers check, not who you use it on.
Divine Sense - The Dark Powers protect against using magic to see the evil in the hearts of man, but They have never completely blocked the ability to detect monsters. There are no spells to detect the alignment of mortals in 5e, so you have to consider just what the ability does. Divine Sense lets you detect the presence and location of Celestials, Fey, Fiends and Undead, and detect if an area or object has been Hallowed/Desecrated. Paladins and Clerics in Ravenloft could sense the presence of the reality wrinkle created by Celestials and Fiends, so that isn't impossible. Fey have never received any special protection from the land and Undead have instead received bonuses to avoid being detected by magic.
I'd suggest the following changes rather than remove an ability entirely. Paladins instead sense the presences of Fey and Undead that fail a Will save (undead getting a bonus or advantage or however you want to handle that) but do not know their location or identity. They can detect the sanctity of an object or place, such as a Sinkhole of Evil, unless there is some sort of magic that would prevent them from doing so. It also tells them if they are within the reality wrinkle of a Celestial or Fiend, but not where or who the creature is or whether it is a Celestial or Fiend; just that they there is something "wrong".
I like the idea of the feeling of foreboding and being watched and would suggest that it be the feeling of being within a Sinkhole of Evil. Darklords also have a history of being able to detect paladins, so perhaps a Paladin who has been noticed also gets that foreboding feeling in addition to the normal information whenever they use the ability until they leave the domain.
I'll take a look a more indepth look at the rest of the abilities later on, but I like what you've done.
I've already thoguht of that and instead came up with a twist. Instead of removing the ability entirely, they instead just get a feeling if somethign is natural of unnatural. And of course that is left up to the interpretation fo the DM as to what could be considered natural or unnatural. Special circumstance rules I am wroking on to.
As far as cutting words, been thinking about it. It's something to consider. This was a fast draft and I am working ona second draft now. Even working on a bigger project to send to Wizards directly maybe to see if I can get the OK for something bigger I have planned. 
Needless to say I've been digging deep into ALL my Ravenloft books starting with the black book all the way up to the 3rd edition version created by White Wolf and fine tuning a lot of things and revising others.
These are some great rules and adaptations. Thanks for all your hard work on fleshing these out, and posting them. I look forward to seeing where you take these.
Update on this project of mine. Sorry it's slow going, but I've been having to take care of a sick family member, so it's been taking up more time, especially with having to go between hospitals and various doctors appointments. Needless to say I am not done with this. The next draft I am designing to look way more professional than simple writing, with fancier sections. Again, like the current one at the least of this post, it won't be a replacement for any Ravenloft book. I expect it, once all is said and done, to take probably another few weeks before I post up the new PDF draft and I hope to get some people to help test it out and give feed back for me for the final.
Changes to look forward to; I went through and basically double checked all the class powers and refined them for Ravenloft. I made some rules changes that I think also pertain to the spirit of Ravenloft in 2nd edition and I've helped clarify some racial things. Currently I am working on the classes, I hope to supply new background types, update the deities, transfer a few feats over (obviously many of the Ravenloft feats just wouldn't fit), and have some rules for things such as firearms and altered magic in place since a lot of spells in 5th edition don't act like they did in 2nd or 3rd.
If time permits, I will do a special Who's Doomed of Ravenloft update to update specific Ravenloft personalities for 5th edition as well as the Domain Lords.
For my latest update PDF for the 5e rules for Ravenloft, I posted a thread in the 5e section here.
Great work!! I am looking forward to using it 
Good stuff! I see that all your rules are based off the idea that I already have the books that those original rules are based off from. What book(s) would you recommend a DM needs to run a Ravenloft campaign? I want to run one now after reading this.
Just found the thread, like others, fun stuff, thanks!