Beach balls when switching between documents

I have a project with around eleven folders, each with around twelve files of text. One of these folders is giving me an issue. When I have the folder open in scrivenings mode, and I move from one document to another, that is, when I click from the former to the latter, I get a beach ball. This has begun to disrupt my workflow and hinder my writing. I usually have to wait between 5 and 10 seconds before I can type or scroll or click again. Help!!

Questions: is this one folder corrupt, because it doesn’t happen in other folders?
If so, how can I move the text somewhere else? (I already copy pasted it once.

It’s not my computer that is the problem because I ran a bunch of tools to check and this is really the only problem it’s having.

I’ve also tried to work without the scrivenings mode on, but it didn’t help much (another post I read suggested that the delay was from refreshing the whole folder). Also, the scrivenings mode is important for the project.

This is the post I read and I tried many of the ideas suggested but nothing helped. I have not wiped or reinstalled my computer.

I’m using version 2.8 on a Mac OS X 10.11.6

This is my first post so let me know if I haven’t provided enough information and what I might need to look for.

Many thanks!