Todd,
is the function of "search DB" for P25 frequencies and modes only?
Yes. The P25RX was originally for P25. The additional protocols: DMR, NXDN, FMNB have been added by request. The majority of the file size for the BTCFG-II / BTConfig software is due to the P25 FCC records for the SearchDB. Other modes could be added, but they will dramatically increase the size. I would really rather use the RR web interface, but I couldn't figure out how to get that done with Java 1.8. The tools I use are not secure in later versions than that. (I won't use them). I could possibly start separating out various parts of the SearchDB and expand it. It may be a while before I can get this done. The upcoming releases will add many more columns to the "roaming flash" to support scanning of all the different modes. So far, P25 P1, P2, DMR, NXDN 4800, 9600, FMNB, AM, ACARS.