1.3.0 Cannot build a Genesis collection

I’m wondering why it seems that I cannot build a genesis collection in RetroArch 1.3.0 when all of my files are no-intro.md files.

Happy to troubleshoot, but I’d like to know where to start.

Xubuntu 16.04 with RA 1.3.0 had the same problem on 14.04, however.