Yes you can. Once your game selected in emulationstation, press select to open a menu, and edit the metadata. You can select the emlulator for this specific game in this menu. Save, start, and check in retroarch menu with hotkey+b.
Hello Eric, yes of course I think you can use mame2003 as neogo.core, with the right name of course for mame2003 For the neo geo roms selection well there is no simple answer I think, I would simply advise you to do it manually, there are not that many neogeo games I would say 50 or so, at most 100. You can help yourself with a recent MameUI version on a PC wich would allow you, without any set, to display neogeo roms from menu options (based on internal DAT) Other than that, yes it would require .Dat or clrmamepro or both
Just one more question... When using a FAT32 formatted USB HDD for the share partition, is there any way to keep the drive from going to sleep and causing no roms to be available to open after the first one? My particular drive has no utility to change the sleep setting in the disk itself, so I was wondering if there was a way to have recalbox "keep alive" the drive by perhaps refreshing a directory listing of /recalbox/share/ or perhaps having it touch /recalbox/share/system/recalbox.conf every 60 seconds or so regardless of whether or not you're in emulation station, retroarch or even dropped out to a command prompt? Thanks in advance for any help.