I tried to download the v1.7.0.3 and installed. However, I find the following error message:
C:\Program Files\paint.net\Effects\DHShapeMaker.dll,Version 1.7.0.3
System.IO.FileNotFoundException: Could not load file or assembly 'System.Runtime, Version=6.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a' or one of its dependencies. System could not find the file.
File name: 'System.Runtime, Version=6.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a'