This question is already assumed answered, so I don't know if the following will help much...
For satellite orbit files (path .sa file), please see the Modeler 18.5 documentation for the Wireless Module, Modeling Wireless Networks -> Orbits for importing STK Orbit files (STK 3.0 or higher).
For mobile node trajectory files (Ephemeris .e file), please see the Modeler 18.5 documentation for the Wireless Module, Modeling Wireless Networks -> Trajectories -> Importing STK Ephemeris files.
I noticed in your description that you included an asterisk (*) in the file name. That is probably why you received the general failure. According to Procedure 6, you choose either a single STK file or All STK files under a chosen directory.
I am having a similar problem, but using the method of choosing a single STK file or All STK files is not working for me. I've also looked at the "Modules > Wireless > Modeling Wireless Networks > Orbits" article, but didn't come to a solution.
Basically when I either try to import a single STK file or All STK files, it generally returns this:
Unable to convert STK file (C:\Users\guan\Documents\STK 11 (x64)\MANET_Article_Simulation\LEO_1.sa): general failure
I am using Modeler 17.5 PL6, and STK 11.2.0.
However, importing STK ephemeris files (*.e) works just fine.
Do I have to configure the STK preferences in some way, or am I thinking wrong?