diff --git a/Application/Bootstrap/Bootstrap.c b/Application/Bootstrap/Bootstrap.c
index f12fc21d..4f7bd639 100644
--- a/Application/Bootstrap/Bootstrap.c
+++ b/Application/Bootstrap/Bootstrap.c
@@ -117,7 +117,7 @@ StartOpenCore (
 
   if (Bootstrap->Revision != OC_BOOTSTRAP_PROTOCOL_REVISION) {
     DEBUG ((
-      DEBUG_ERROR,
+      DEBUG_WARN,
       "BS: Unsupported bootstrap protocol %u vs %u\n",
       Bootstrap->Revision,
       OC_BOOTSTRAP_PROTOCOL_REVISION
diff --git a/Changelog.md b/Changelog.md
index d6c2c82b..43bf91a1 100644
--- a/Changelog.md
+++ b/Changelog.md
@@ -9,6 +9,7 @@ OpenCore Changelog
 - Added basic AMD Zen CPU support
 - Added `Misc` -> `Tools` section to add third-party tools
 - Added `Kernel` -> `Emulate` section for CPUID patches
+- Added `CustomSMBIOSGuid` quirk for Custom SMBIOS update mode
 
 #### v0.0.2
 - Documentation improvements (see Differences.pdf)
diff --git a/Docs/Configuration.pdf b/Docs/Configuration.pdf
index c6440411..82692271 100644
Binary files a/Docs/Configuration.pdf and b/Docs/Configuration.pdf differ
diff --git a/Docs/Configuration.tex b/Docs/Configuration.tex
index 0647566c..42b56879 100755
--- a/Docs/Configuration.tex
+++ b/Docs/Configuration.tex
@@ -1230,6 +1230,13 @@ blocking.
   about the issue can be found in
   \href{https://github.com/acidanthera/AptioFixPkg#verifymsre2}{VerifyMsrE2} notes.
 
+\item
+  \texttt{CustomSMBIOSGuid}\\
+  \textbf{Type}: \texttt{plist\ boolean}\\
+  \textbf{Default value}: \texttt{false}\\
+  \textbf{Description}: Performs GUID patching for \texttt{UpdateSMBIOSMode}
+  \texttt{Custom} mode. Usually relevant for Dell laptops.
+
 \item
   \texttt{DisableIoMapper}\\
   \textbf{Type}: \texttt{plist\ boolean}\\
@@ -2092,8 +2099,8 @@ be used. Version with macOS specific enhancements can be downloaded from
     to workaround firmwares overwriting SMBIOS contents at
     ExitBootServices. Otherwise equivalent to \texttt{Create}. Requires
     patching AppleSmbios.kext and AppleACPIPlatform.kext to read from
-    another GUID: \texttt{"EB9D2D31"} -\textgreater{}
-    \texttt{"EB9D2D35"} (in ASCII).
+    another GUID: \texttt{"EB9D2D31"} - \texttt{"EB9D2D35"} (in ASCII),
+    done automatically by \texttt{CustomSMBIOSGuid} quirk.
   \end{itemize}
 \item
   \texttt{Generic}\\
diff --git a/Docs/Differences/Differences.pdf b/Docs/Differences/Differences.pdf
index a2917cf1..38892815 100644
Binary files a/Docs/Differences/Differences.pdf and b/Docs/Differences/Differences.pdf differ
diff --git a/Docs/Differences/Differences.tex b/Docs/Differences/Differences.tex
index 502ec2b8..086afc79 100644
--- a/Docs/Differences/Differences.tex
+++ b/Docs/Differences/Differences.tex
@@ -1,7 +1,7 @@
 \documentclass[]{article}
 %DIF LATEXDIFF DIFFERENCE FILE
 %DIF DEL PreviousConfiguration.tex   Fri May 24 02:34:39 2019
-%DIF ADD ../Configuration.tex        Fri Jun  7 16:53:47 2019
+%DIF ADD ../Configuration.tex        Fri Jun  7 21:56:18 2019
 
 \usepackage{lmodern}
 \usepackage{amssymb,amsmath}
@@ -1326,7 +1326,15 @@ blocking.
   \href{https://github.com/acidanthera/AptioFixPkg#verifymsre2}{VerifyMsrE2} notes.
 
 \item
-  \DIFaddbegin \texttt{\DIFadd{DisableIoMapper}}\\
+  \DIFaddbegin \texttt{\DIFadd{CustomSMBIOSGuid}}\\
+  \textbf{\DIFadd{Type}}\DIFadd{: }\texttt{\DIFadd{plist\ boolean}}\\
+  \textbf{\DIFadd{Default value}}\DIFadd{: }\texttt{\DIFadd{false}}\\
+  \textbf{\DIFadd{Description}}\DIFadd{: Performs GUID patching for }\texttt{\DIFadd{UpdateSMBIOSMode}}
+  \texttt{\DIFadd{Custom}} \DIFadd{mode. Usually relevant for Dell laptops.
+}
+
+\item
+  \texttt{\DIFadd{DisableIoMapper}}\\
   \textbf{\DIFadd{Type}}\DIFadd{: }\texttt{\DIFadd{plist\ boolean}}\\
   \textbf{\DIFadd{Default value}}\DIFadd{: }\texttt{\DIFadd{false}}\\
   \textbf{\DIFadd{Description}}\DIFadd{: Disables }\texttt{\DIFadd{IOMapper}} \DIFadd{support in XNU (VT-d),
@@ -1816,11 +1824,10 @@ rm vault.pub
   \item \texttt{OC\_SCAN\_ALLOW\_DEVICE\_SCSI}
   \item \texttt{OC\_SCAN\_ALLOW\_DEVICE\_NVME}
   \end{itemize}
-\DIFaddbegin 
 
 \end{enumerate}
 
-\subsection{\DIFadd{Tools Properties}}\label{misctoolprops}
+\DIFaddbegin \subsection{\DIFadd{Tools Properties}}\label{misctoolprops}
 
 \begin{enumerate}
 \item
@@ -1845,12 +1852,12 @@ rm vault.pub
   \textbf{\DIFadd{Default value}}\DIFadd{: Empty string}\\
   \textbf{\DIFadd{Description}}\DIFadd{: File path to select UEFI tool relative to }\texttt{\DIFadd{OC/Tools}}
   \DIFadd{directory.
-}\DIFaddend 
+}
 
 \end{enumerate}
 
 
-\section{NVRAM}\label{nvram}
+\DIFaddend \section{NVRAM}\label{nvram}
 
 \subsection{Introduction}\label{nvramintro}
 
@@ -2196,8 +2203,9 @@ be used. Version with macOS specific enhancements can be downloaded from
     to workaround firmwares overwriting SMBIOS contents at
     ExitBootServices. Otherwise equivalent to \texttt{Create}. Requires
     patching AppleSmbios.kext and AppleACPIPlatform.kext to read from
-    another GUID: \texttt{"EB9D2D31"} -\textgreater{}
-    \texttt{"EB9D2D35"} (in ASCII).
+    another GUID: \texttt{"EB9D2D31"} - \DIFdelbegin \DIFdel{\textgreater{}
+    }\DIFdelend \texttt{"EB9D2D35"} (in ASCII)\DIFaddbegin \DIFadd{,
+    done automatically by }\texttt{\DIFadd{CustomSMBIOSGuid}} \DIFadd{quirk}\DIFaddend .
   \end{itemize}
 \item
   \texttt{Generic}\\
diff --git a/Platform/OpenCore/OpenCoreKernel.c b/Platform/OpenCore/OpenCoreKernel.c
index 00180f82..1886ddcc 100644
--- a/Platform/OpenCore/OpenCoreKernel.c
+++ b/Platform/OpenCore/OpenCoreKernel.c
@@ -306,6 +306,10 @@ OcKernelApplyPatches (
     if (Config->Kernel.Quirks.DisableIoMapper) {
       PatchAppleIoMapperSupport (Context);
     }
+
+    if (Config->Kernel.Quirks.CustomSmbiosGuid) {
+      PatchCustomSmbiosGuid (Context);
+    }
   } else {
     if (Config->Kernel.Quirks.AppleXcpmCfgLock) {
       PatchAppleXcpmCfgLock (&Patcher);