title: How to update MVVMCross from 5.1.1 to 5.2.0
body: <p>I updated MVVMCross 5.1.1 to 5.2.0 in a sample project (TipCalc) with Android and UWP.
  Nuget offered this update an I just updated using VS2017 nuget view.</p>
  
  <p>After this two things happend:The UPW designer tells me that views:MvxWindowsPage doesn't exist in the namespace MvvmCross.Uwp.Views.
  So I have no longer a working designer.</p>
  
  <p>Rebuild brings up these warnings</p>
  
  <pre><code>...TipCalc.UI.Droid.csproj : warning XA0105: The $(TargetFrameworkVersion) for MvvmCross.Binding.Droid.dll(v7.0) is greater than the $(TargetFrameworkVersion) for your project(v6.0). You need to increase the $(TargetFrameworkVersion) for your project.
  ...TipCalc.UI.Droid.csproj : warning XA0105: The $(TargetFrameworkVersion) for MvvmCross.Droid.dll (v7.0) is greater than the $(TargetFrameworkVersion) for your project(v6.0). You need to increase the $(TargetFrameworkVersion) for your project.
  ...TipCalc.UI.Droid.csproj : warning XA0105: The $(TargetFrameworkVersion) for MvvmCross.Platform.Droid.dll (v7.0) is greater than the $(TargetFrameworkVersion) for your project(v6.0). You need to increase the $(TargetFrameworkVersion) for your project.
  </code></pre>
  
  <p>Starting it on the emulator crashes the app.
  The droid project is set to Marshmellow (6.0).</p>
  
  <p>Does the MVVMCross 5.2 version need Lollipop (7.0) - or did I something wrong when updating?</p>