Update README for new build process

Author: sinai-dev

README.md

@@ -147,15 +147,43 @@ public class MenuClass_CursorUpdate
 
 ## Building
 
-If you'd like to build this yourself, everything you need (other than MelonLoader and/or BepInEx) is included with this repository.
+If you'd like to build this yourself, you will need to have installed BepInEx and/or MelonLoader for at least one Unity game. If you want to build all 6 versions, you will need at least one Il2Cpp and one Mono game, with BepInEx and MelonLoader installed for both.
 
 1. Install MelonLoader or BepInEx for your game.
 2. Open the `src\Explorer.csproj` file in a text editor.
 3. Set the relevant `GameFolder` values for the versions you want to build, eg. set `MLCppGameFolder` if you want to build for a MelonLoader Il2Cpp game.
 4. Open the `src\Explorer.sln` project.
 5. Select `Solution 'Explorer' (1 of 1 project)` in the Solution Explorer panel, and set the <b>Active config</b> property to the version you want to build, then build it.
 5. The DLLs are built to the `Release\` folder in the root of the repository.
-6. [ILRepack](https://github.com/gluck/il-repack) is used to merge `lib\mcs.dll` and the release dll, this step is optional. If you don't merge them, you will need to put `mcs.dll` in the folder with the mod when you install it.
+
+[ILRepack](https://github.com/gluck/il-repack) is used to merge `lib\mcs.dll` and the release dll. Download the ILRepack nuget package and take the `ILRepack.exe` file from it.
+
+Put `ILRepack.exe` in the `Release\` folder, then create a `merge.bat` file like so:
+
+```batch
+:: Set GameFolder to the full path of the game you have installed MelonLoader and/or BepInEx for.
+SET GameFolder="..."
+
+:: Only include the lines for the version(s) you are building.
+
+:: MelonLoader Il2CPP:
+ILRepack.exe /lib:"%GameFolder%\MelonLoader" /lib:"%GameFolder%\MelonLoader\Managed" /out:"Explorer.MelonLoader.Il2Cpp\Explorer.dll" "Explorer.MelonLoader.Il2Cpp\Explorer.dll" "..\lib\mcs.dll"
+
+:: MelonLoader Mono
+ILRepack.exe /lib:"..\lib" /lib:"%GameFolder%\MelonLoader" /out:"Explorer.MelonLoader.Mono\Explorer.dll" "Explorer.MelonLoader.Mono\Explorer.dll" "..\lib\mcs.dll"
+
+:: MelonLoader Mono .NET35	
+ILRepack.exe /lib:"..\lib" /lib:"%GameFolder%\MelonLoader" /out:"Explorer.MelonLoader.Mono.NET35\Explorer.dll" "Explorer.MelonLoader.Mono.NET35\Explorer.dll" "..\lib\mcs.NET35.dll"
+	
+:: BepInEx Il2Cpp
+ILRepack.exe /lib:"%GameFolder%\BepInEx\core" /lib:"%GameFolder%\BepInEx\unhollowed" /out:"Explorer.BepInEx.Il2Cpp\Explorer.dll" "Explorer.BepInEx.Il2Cpp\Explorer.dll" "..\lib\mcs.dll"
+	
+:: BepInEx Mono
+ILRepack.exe /lib:"..\lib" /lib:"%GameFolder%\BepInEx\core" /out:"Explorer.BepInEx.Mono\Explorer.dll" "Explorer.BepInEx.Mono\Explorer.dll" "..\lib\mcs.dll"
+	
+:: BepInEx Mono .NET35	
+ILRepack.exe /lib:"..\lib" /lib:"%GameFolder%\BepInEx\core" /out:"Explorer.BepInEx.Mono.NET35\Explorer.dll" "Explorer.BepInEx.Mono.NET35\Explorer.dll" "..\lib\mcs.NET35.dll"
+```
 
 ## Credits