So I recently bought the Dragonborn DLC, and i was wondering for a few days how to get to solstheim. I looked it up on the wiki, and found out that you had to take the boat. After quite some exploring, questing and what not I was beginning to worry about the main questline, as it should be normal that it starts soon, I thought. After some more reading the wiki, I saw that you had to be approached by Cultists, kill them, and take a letter from them. They would appear during daytime in any major Hold. After I read this, I immediatly went to Windhelm and Whiterun (during daytime of course), but to no avail. I was not approached by cultists. After some more thinking the possibility of already having killed the cultists crossed my mind. To my surprise, I had one full set of "cultist" armor in my inventory (I have kind of a bad habit where I like to loot armour), but I did not recall having killed (a) cultist(s), and there was no letter in my inventory. Again, I checked the wiki for more information, and this time I found that when you have killed the cultists but not yet looted them, you get a quest marker indicating the body that the letter can be looted from, implying that the quest "Dragonborn" (I think that was the name) has already started. I tried standing and waiting in cities some more but it just wouldn't work, and I am out of ideas. I would absolutely love some help with this, so thanks already. I am on PC so console commands or whatever works is also welcome.
Thank you for reading, and I hope you can help. Thanks!
PS: I seem to be prone to glitches for some reason, because I have been experiencing a few other minor problems. First of all, ore in mines does not seem to want to replenish, even after a lot of months (most certainly more than thirty days). When I look at the ore veins, the color has returned and it looks mineable, but it seems the collision box is nonexistent, I do not get an option to mine, I cannot hit it with a pickaxe and strangest of all, I can walk through it..... If you have advice, I'd love to hear it.
PPS: another little something I have been having trouble with is that Shadowmere doesn't seem to respawn, even after 10 days. The wiki said it would reappear after 10 days on the spot it died on (which I unfortunately I couldn't find). This raises the question if it will fast-travel with you again the moment it is alive. For me this didn't happen. Some advice (maybe console commands?) would be great.