MAME Roms load but none of the buttons work.

[XtraKargo]

I am doing great with most of the other emulators, and was stumped once I got to MAME.   After being taken to task on which RomSet works with Retro Pie I have made some progress by getting them to load.  But once it loads none of the keys are recognized.  I have to power it off with the hard switch and then play something else.  Any insight on getting the arcade games to run?

I have them loaded in the mame-mame4all folder for the time being. 

Thanks in advance for the help!