diff --git a/test/iso/install_os-release.sh b/test/iso/install_os-release.sh
index 37e0007..788111a 100644
--- a/test/iso/install_os-release.sh
+++ b/test/iso/install_os-release.sh
@@ -1,6 +1,6 @@
 #!/bin/bash
 
-FOUND_VERSION=$(grep VERSION_ID mnt/install/etc/os-release | cut -d= -f2)
+FOUND_VERSION=$(grep VERSION_ID mnt/install/etc/os-release | cut -d= -f2 | tr -d '"')
 
 if [[ ${FOUND_VERSION} != ${VERSION} ]]
 then
diff --git a/test/vm/Makefile b/test/vm/Makefile
index 1c3ef4b..99288cb 100644
--- a/test/vm/Makefile
+++ b/test/vm/Makefile
@@ -32,7 +32,7 @@ files/mnt/iso:
 	sudo mount -o loop ../../$(ISO_NAME) files/mnt/iso
 
 files/grub.cfg: files/mnt/iso
-	cp files/mnt/iso/boot/grub2/grub.cfg files/grub.cfg
+	cp files/mnt/iso/$(if $(_RHEL),isolinux/grub.conf,boot/grub2/grub.cfg) files/grub.cfg
 	sed -i 's/quiet/console=ttyS0,115200n8 inst.ks=cdrom:\/ks.cfg/' files/grub.cfg
 	sed -i 's/set default="1"/set default="0"/'                     files/grub.cfg
 	sed -i 's/set timeout=60/set timeout=1/'                        files/grub.cfg
@@ -57,7 +57,7 @@ files/install.iso: files/grub.cfg
 	-compliance joliet_long_names
 	-map files/ks.cfg ks.cfg
 	-chmod 0444 ks.cfg
-	-map files/grub.cfg boot/grub2/grub.cfg
+	-map files/grub.cfg $(if $(_RHEL),isolinux/grub.conf,boot/grub2/grub.cfg)
 	-end
 	EOF
 
diff --git a/xorriso/Makefile b/xorriso/Makefile
index 65b8b2a..b2f5d87 100644
--- a/xorriso/Makefile
+++ b/xorriso/Makefile
@@ -1,5 +1,6 @@
 input.txt: gen_input.sh
-	sed -i 's/quiet/quiet $(EXTRA_BOOT_PARAMS)/g' ../results/boot/grub2/grub.cfg
+	find
+	$(if $(wildcard ../results/boot/grub2/grub.cfg),sed -i 's/quiet/quiet $(EXTRA_BOOT_PARAMS)/g' ../results/boot/grub2/grub.cfg)
 	sed -i 's/quiet/quiet $(EXTRA_BOOT_PARAMS)/g' ../results/EFI/BOOT/grub.cfg
 	$(eval _VARS = ARCH FLATPAK_DIR IMAGE_NAME IMAGE_TAG ISO_NAME VERSION)
 	$(foreach var,$(_VARS),$(var)=$($(var))) bash gen_input.sh | tee input.txt
diff --git a/xorriso/gen_input.sh b/xorriso/gen_input.sh
index a0f3a48..0329186 100644
--- a/xorriso/gen_input.sh
+++ b/xorriso/gen_input.sh
@@ -14,8 +14,11 @@ do
     then
         continue
     fi
-    echo "-map ${PWD}/${file} ${file:2}"
-    echo "-chmod 0444 ${file:2}"
+    if [[ -f ${PWD}/${file} ]]
+    then
+        echo "-map ${PWD}/${file} ${file:2}"
+        echo "-chmod 0444 ${file:2}"
+    fi
 done
 popd > /dev/null