psx not support zip/rar files, check readme.txt file in psx rom folder.
## RECALBOX - SYSTEM PSX ## Put your playstation roms in this directory. Rom files must have a ".iso/.img/.pbp/.cue/.ccd/.cbn/.m3u/.chd" extension. .bin files need a .cue file to be started. These cores needs 3 new BIOS (names are case sensitive) : scph5500.bin - 8dd7d5296a650fac7319bce665a6a53c scph5501.bin - 490f666e1afb15b7362b406ed1cea246 scph5502.bin - 32736f17079d0b2b7024407c39bd3050