Patch worked
Patch worked for me on FS510.kip. You look for hex 9A E3 FF 97 and change it to 1F 20 03 D5. All XCIs converted to NSPs have worked for me so far without installing an update.
What my setup looks like and I have no problems.
modules/oldlayered/loader.kip1
modules/oldlayered/sm.kip1
modules/oldlayered/fs_mitm.kip1
FS510-exfat_nocmac_nosigchk.kip1
atmosphere=1