Company,
The last 2 apps you mentioned are "Modelers". They will make the model/geometry.
The "toolpath and G-code output" will be handled by a different program.... I think Alibre partners with "VisualMill" by Mecsoft. I didnt see a CAM partner for Spaceclaim.
But you are also not limited to using that partner software... You can save your model from the design package and load it into many different CNC packages... But if you are getting going on it, maybe the integrated one will be an easier start (Alibre with the Mecsoft Plugin)
Here is the link to mecsofts Lathe/turning module:
MecSoft VisualTURN: program 2-axis CNC turning centers or lathes.