Hello,
I am new to this community. I've been playing this game off an on since childhood and recently started watching through the speed run vids. Very impressive I gotta say.

I have been trying to do a run as well and have run into a couple of possible bugs with Harah.

First bug: Harah stays in Ergsin Timin after I visited a village.
- So with this one, I am following the route where you take her and discover the other village in the east (not the fish mouth). I purchased an orni and then talked to Harah. She gives the line of wanting to be taken back to Tuono Timin, as expected. So I fly to Tuono Timin, but I didn't leave here there because I forgot about Gurney.
- So I fly to the palace just to pick up Gurney, I leave Stilgar. I fly to my troops in Ergsin Timin and leave Gurney there.
- Then for some reason, Harah says "I'm staying here".
- I flew back to Ergsin Timin to see if I could bring Harah with me, but she keeps giving the line of "I'll follow you, but now too far."

- Has anyone ever experienced this? The game progresses normally after that. When I go get Stilgar, he tells me about Chani, but we have to fly there to meet here (no Chani glitch).

Second Harah Bug: Harah won't leave me alone.
- So for this one, I am playing through the game like normal and going with the storyline. I go to the village in the fish's mouth after Harah tells me about it. Then I visited some other sietches and then found the other village in the Carthag / Tuono area.
- After visiting this second village, I talk to Harah and she tells me she wants to go home.
- I take Harah to Tuono Timin and tell her to stay here. She says "I'll stay here if I want to! Sheesh" and doesn't politely thank me for bringing her home.
- Stilgar then won't tell me about Chani because Harah hasn't "left" yet.
- I tried picking Harah back up, flying around, going to a village, provoking her, leaving her in the desert outside a village, flying away, taking her back to Tuono Timin, but she just seems upset at me.

Any thoughts on these? Thank you!

Hello! Welcome to the very small tribe of Dune speerunners
I see. Very interesting What you're experiencing is in fact the "Gurney Halleck" bug. (I wrote a guide about the game's bugs here : https://www.speedrun.com/dune1992/guide/kyybu ).
Explanation: there is a number in the game's memory that indicates your progression in the scenario. Most of the game events set this number to a fixed value, but leaving Gurney in a sietch to train Fremen for the first time increments it. In some cases, it can be incremented beyond the value of the next game event. The event then occurs right away. In your case, the event "leaving Harah home".
I never exeprienced this particular occurence of the bug. Very interesting, thank you for this detailed report
Be careful though, as in precise conditions this bug makes Chani disapear from the game, making you unable to finish it.

For the second bug, it has been a long time since I played the game, but I guess you're missing an event, probably in the palace. Maybe there is a pending message in the communication room, or you forgot to talk to a character in the palace. (or perhaps you need to launch a first attack against the Harkonnen, but that seems unlikely).