So the crystal isn't even visible and trying to mod the files leads to error loading the map. What to do?
This is not the $35 patreon version, though it is 11.5. Have you tried using the save editor linked in the first post?
Can you give me discord post link please ?
... No? As that's kind of not how discord works. There's an invite link to the channel under the general information tab in the first post. Discord itself is a program that needs to be installed first, and at some point you should make a username so you can access the channel. If you somehow end up paying for the program itself, you made a wrong turn somewhere. Conversations from before you arrived remain visible, so it's not as if you have to bring up a topic "again" unless you manage to not find what you're looking for.
If you don't care to do any of that, there's always making a patreon account (which does not require being subscribed to anyone or paying for membership) and seeing what's currently visible as a non-patron on MuseX's page. You can ask questions and potentially receive answers there as well.
If you find all of the above to be "too much trouble" or smelling too much like a "shill," I've got nothing for you.
I am following the provided walkthrough and most of the thing don't trigger in day 3 as it states in the guide.
The walkthrough, as you'll find several times over the pages here, is very out-of-date. Most to all day 3 events were moved to day 8, and day 4 to day 9, and so on. Some things, like needing to have the house "fixed" by a certain day or cleaning the village, are not currently active.
If you go to sleep at 2100 like an early bird, you'll wake up around 0500 and have plenty of time to run over to Vincent's before 6. Triggering Roxie's event with him is a 50% chance, anyway, though. Mia will arrive on the morning of Day 8. Sophie will be hanging around the entrance to your area after you clear the afternoon event at the well with Nina and Trevor on the same day, or (if you miss the timing that day for whatever reason) a following day.