A few months ago, I noticed this topic but didn’t have the time to fully read through it. Yesterday, I stayed up all night and read everything from start to finish. Oh my God, it’s been months and there’s still no good solution to this issue. Over the past few months, I’ve also tested many different days. My most serious problem is caused by the WhyEm DLC. I’m using WhyEm’s DLC Red Dead Offline Edition, and I modified his shop_items.ymt file to make it use the textures that are already in the game. It has some effects. Since I only use his saddles and horse masks, I don’t have high requirements, so switching to the game’s original textures works with some effects.
The WhyEm DLC-modified Red Dead Offline Edition file also caused a serious problem.
The optional file—the WhyEm DLC Red Dead Offline Edition compatibility file—causes the coffee pot to be impossible to purchase (this is a permanent bug that must be resolved during the “Self-Respect, Injured and Departing” mission). This happens right at the start of Chapter 2, before Hosea takes Arthur hunting. The solution is to exit the game, uninstall the Red Dead Offline Edition compatibility file, then re-enter the game and buy the coffee pot before saving the game. Afterward, exit the game and reinstall the Red Dead Offline Edition compatibility file. That should fix it. Otherwise, you won’t be able to buy the coffee pot later on.
Also, when purchasing enhanced gear from the trapper, it will prevent the extra level-ups for Health, Stamina, and Dead Eye from working. It’s stuck at level 8, and you won’t be able to reach level 10 anymore (this is also a permanent bug). The solution is the same: exit the game, uninstall the Red Dead Offline Edition compatibility file, then buy the enhanced gear before saving the game. After that, exit and reinstall the Red Dead Offline Edition compatibility file. It should work normally, but if you don’t do this, you won’t reach level 10.
It looks like I’ll just have to continue waiting.