Location Control is OFF, so that isn't an issue. I've checked all of the frequencies I entered in for all of the sites, and they are all correct. Most--if not all--of the TGs I have are simulcast across all sites. I can't seem to find any reason why it wouldn't pick up the channels. I've included the .hpd file. Maybe someone can show me what I'm missing here.
You have to save it as a hpe file.
In Sentinel, File>Export to hpe file...