I can confirm that PicoDrive 1.91 core for RetroArch plays the game in 32X mode using Sega CD BIOS files. EDIT: If you get slow video, try the GDI video driver ([gears]\Driver\Video Driver\gdi). If you get hiccups every few seconds with the GDI driver, try playing in windowed mode instead of full screen.
Methods: Use "Online Updater \ Core Updater" to "update"/install "Sega MS/MD/CD/32X (PicoDrive)" core. Rename relevant Sega CD BIOS files to "bios_CD_E.bin", "bios_CD_J.bin", "bios_CD_U.bin" and place in the "...\RetroArch\System" folder. Load the core using "Load Core", load the .CUE or .ISO file (both work) using "Load Content".
p.s. Genesis Plus GX v1.7.4 RetroArch core displays "POWER DOWN AND CONNECT THE 32X"