Its not a SDK thing, its on boot that it happens, everyone that is using gateway is still booting from 4.x Regardless of what version of EmuNAND you are using, it is not booting into that version, its loading into it through 4.x, Hence the new flags etc arent even in existence, so anything using the new 7.x Encryption method will fail to load, once games are using it we will be even more screwed
From 3dBrew
As of
7.0.0-13 the system now supports a new encryption method for the secure-cryptotype, the CTR for this is the same as before. This is enabled when NCCH flag[3] is non-zero. When enabled, the
RomFS and
ExeFS files which don't have filenames "icon" or "banner"(that is, ".code") are crypted with a different keyslot. This keyslot is
initialized by the 6.0 gamecard savegame keyY init function during boot, using a different portion of the
final hash(this keyslot is separate from the one used for the 6.0 save crypto).