Programs with MonoGame.Extended.Content and Importer/Exporter

I am having problems with the importer/exporter for MonoGame.Extended.Content.Pipeline. I found this post recently: https://community.monogame.net/t/solved-cant-find-a-default-importer-for-tiled-tmx-files/10776e and tried out the solution however when I tried to add the dll package I got an error. (I went to user profile–> packages and found the dll fil and tried to add it to references.) The first time I accidently imported some random dll package but now whenever I remove it and try to add the one you mentioned I get this error:

System.Reflection.ReflectionTypeLoadException: Unable to load one or more of the requested types. Retrieve the LoaderExceptions property for more information.
at System.Reflection.RuntimeModule.GetTypes(RuntimeModule module)
at System.Reflection.Assembly.GetTypes()
at MonoGame.Tools.Pipeline.PipelineTypes.ResolveAssemblies(IEnumerable`1 assemblyPaths)
at MonoGame.Tools.Pipeline.PipelineTypes.Load(PipelineProject project)
at MonoGame.Tools.Pipeline.PipelineController.ResolveTypes()
at MonoGame.Tools.Pipeline.PipelineController.OnReferencesModified()
at MonoGame.Tools.Pipeline.CellRefs.Edit(PixelLayout control)
at System.Windows.Threading.ExceptionWrapper.InternalRealCall(Delegate callback, Object args, Int32 numArgs)
at System.Windows.Threading.ExceptionWrapper.TryCatchWhen(Object source, Delegate callback, Object args, Int32 numArgs, Delegate catchHandler)
at System.Windows.Threading.DispatcherOperation.InvokeImpl()
at System.Threading.ExecutionContext.RunInternal(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)
at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)
at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state)
at MS.Internal.CulturePreservingExecutionContext.Run(CulturePreservingExecutionContext executionContext, ContextCallback callback, Object state)
at System.Windows.Threading.DispatcherOperation.Invoke()
at System.Windows.Threading.Dispatcher.ProcessQueue()
at System.Windows.Threading.Dispatcher.WndProcHook(IntPtr hwnd, Int32 msg, IntPtr wParam, IntPtr lParam, Boolean& handled)
at MS.Win32.HwndWrapper.WndProc(IntPtr hwnd, Int32 msg, IntPtr wParam, IntPtr lParam, Boolean& handled)
at MS.Win32.HwndSubclass.DispatcherCallbackOperation(Object o)
at System.Windows.Threading.ExceptionWrapper.InternalRealCall(Delegate callback, Object args, Int32 numArgs)
at System.Windows.Threading.ExceptionWrapper.TryCatchWhen(Object source, Delegate callback, Object args, Int32 numArgs, Delegate catchHandler)
at System.Windows.Threading.Dispatcher.LegacyInvokeImpl(DispatcherPriority priority, TimeSpan timeout, Delegate method, Object args, Int32 numArgs)
at MS.Win32.HwndSubclass.SubclassWndProc(IntPtr hwnd, Int32 msg, IntPtr wParam, IntPtr lParam)
at MS.Win32.UnsafeNativeMethods.DispatchMessage(MSG& msg)
at System.Windows.Threading.Dispatcher.PushFrameImpl(DispatcherFrame frame)
at System.Windows.Application.RunDispatcher(Object ignore)
at System.Windows.Application.RunInternal(Window window)
at MonoGame.Tools.Pipeline.Program.Main(String[] args)

I’m not sure what to do at this point. Any ideas? Any help would be appreciated!