If you see an error such as "Could not load type 'GH_Util.BezierF' from assembly 'GH_Util'", please follow the steps below:
This error occurs when a third party plugin (not distributed with Fologram or Rhino) erroneously distributes the Rhino class libraries (RhinoCommon.dll, GH_IO.dll and/or GH_Util.dll) with their plugin.
You can keep using both Fologram and the conflicting plugin, you will simply need to remove the erraneous files. These will be found in the third-party plugin location, which is typically %appdata%/Grasshopper/Libraries
Please also notify the developer that they should not be distributing Rhino's libraries.