Hello, I want to use Project Nevada along Darnified UI, but when I try to install the Darnified UI, it prompts me to overwrite some Project Nevada files.

I want both to run, is there a way to have Darnified UI with Project Nevada?

Just install Darn first, then PN. Works fine.

What ToJKa said.

Pay attention to mod readme's, usually, hopefully, they have some install notes that cover order of install and load order. Also, peruse the thread for the mod at the Nexus boards, sometimes conflict issues can be discovered there.