grub.cfg that crashes TrustedGRUB2

grub.cfg

# Automatically generated.  DO NOT EDIT THIS FILE!

search --set=drive1 --fs-uuid XXXX-XXXX
if [ -s $prefix/grubenv ]; then
  load_env
fi

# ‘grub-reboot’ sets a one-time saved entry, which we process here and
# then delete.
if [ "${saved_entry}" ]; then
  # The next line *has* to look exactly like this, otherwise KDM's
  # reboot feature won't work properly with GRUB 2.
  set default="${saved_entry}"
  set saved_entry=
  set prev_saved_entry=
  save_env saved_entry
  save_env prev_saved_entry
  set timeout=1
else
  set default=0
  set timeout=2
fi

# Setup the graphics stack for bios and efi systems
if [ "${grub_platform}" = "efi" ]; then
  insmod efi_gop
  insmod efi_uga
else
  insmod vbe
fi
insmod font
if loadfont ($drive1)//boot/grub/fonts/unicode.pf2; then
  insmod gfxterm
  if [ "${grub_platform}" = "efi" ]; then
    set gfxmode=auto
    set gfxpayload=keep
  else
    set gfxmode=1024x768
    set gfxpayload=text
  fi
  terminal_output gfxterm
fi

insmod png
if background_image ($drive1)//background.png; then
  set color_normal=white/black
  set color_highlight=black/white
else
  set menu_color_normal=cyan/blue
  set menu_color_highlight=white/blue
fi

insmod part_gpt


menuentry "OS - Default" {
  search --set=drive1 --fs-uuid XXXX-XXXX
  linux ($drive1)//kernels/bzImage1 systemConfig=/nix/store/os1.cfg init=/nix/store/os1.init
  initrd ($drive1)//kernels/initrd1
}

submenu "OS - All configurations" {
menuentry "OS - Configuration 2" {
  search --set=drive1 --fs-uuid XXXX-XXXX
  linux ($drive1)//kernels/bzImage2 systemConfig=/nix/store/os2.cfg init=/nix/store/os2.init
  initrd ($drive1)//kernels/initrd2
}

menuentry "OS - Configuration 3" {
  search --set=drive1 --fs-uuid XXXX-XXXX
  linux ($drive1)//kernels/bzImage3 systemConfig=/nix/store/os3.cfg init=/nix/store/os3.init
  initrd ($drive1)//kernels/initrd3
}

menuentry "OS - Configuration 4" {
  search --set=drive1 --fs-uuid XXXX-XXXX
  linux ($drive1)//kernels/bzImage4 systemConfig=/nix/store/os4.cfg init=/nix/store/os4.init
  initrd ($drive1)//kernels/initrd4
}

menuentry "OS - Configuration 5" {
  search --set=drive1 --fs-uuid XXXX-XXXX
  linux ($drive1)//kernels/bzImage5 systemConfig=/nix/store/os5.cfg init=/nix/store/os5.init
  initrd ($drive1)//kernels/initrd5
}

#
# Adding another menu entry crashes TrustedGRUB2!
# Try by uncommenting the next menuentry.
#
#menuentry "OS - Configuration 6" {
#  search --set=drive1 --fs-uuid XXXX-XXXX
#  linux ($drive1)//kernels/bzImage6 systemConfig=/nix/store/os6.cfg init=/nix/store/os6.init
#  initrd ($drive1)//kernels/initrd6
#}

}