I just learned that I could import an I-deas Universal mesh file to Fluent mesher. Fluent User's Guide for 2022R1 says (on page 1064) that there are three ways to import .unv file to Ansys Fluent. First, import it directly into Fluent (which does not work in my case because of the error). Second, use fe2ram filter, and third, import it to Fluent mesher.

I'm interested on this last option, but it says that I need to use some commands. I could not find anything related to that in the user's guide, so I'm asking here if someone knows the procedure. This could help me with the original problem.