Not sure about the first one.
On the second one (from another post):
If the .cproject file are associated with System Workbench, just double-click on this file to open System Workbench and import the generated project into the workspace.
try to add the association. Open the preferences window, click on Window menu then Preferences. In the Preferences view, select System Workbench in the tree and click on File Association, and Install button: