I bought a blue star fern thinking it had different looking areas on the leaves, but when I really got to looking at them and felt them discovered these areas were papery and felt dead; also greyish looking a felt like this greyish stuff should be rubbed off. I don’t know why the garden center let me buy it without telling me it was diseased. I know very little about plants, so I plead ignorance.
It sounds like it may have been getting overwatered which will cause leave to dry out. I’d trim off nay of the leaves showing damage and water less. Make sure it is getting very bright light but not a lot of direct sun. Here’s a link that does a good job describing the needs of your blue star fern.