Historical issue on loading large NEOGEO roms on NEW3DS

In RetroArch 1.6.7, I can successfully load large NEOGEO roms (such as KOF99-2003, Metal Slug 3) anytime through FBA 2012 and FBA 2012 NEOGEO cores. But from 1.6.8 to the latest 1.7.7, I cannot load these roms anymore. I have tried both cia and 3dsx versions. After deleting all files except roms in RetroArch folder, I can only load large roms directly in the first time. From the second time I have to load a small NEOGEO rom first, then I can change to large NEOGEO roms without closing content. If I load large rom directly, RA crashes. If I load a small rom then close the content or quit RA then load large rom, RA also crashes. The ROM sets are absolutely correct. Because they can be played in 1.6.7 in 3DS or any bulid in PSV. Can this issue be fixed in future? NEW3DS is really an excellent device for NEOGEO games due to its low resolution.