Planebuilder. Sorry it did not work for you, I assume you have a fairly recent version of Ezilathe. Last Upload (as beta) was V1.6.4.4, and this has all the features needed.
The ability to load Reversed Polylines was not in the last full upload V1.6.4. if you are using this version, you will need to make certain that polyline direction is correct in the DXF.

First Make sure you are set to "OD TURNING OPERATION" and for Direction "Follow Polyline". This will only work when set like this (refer included jpg).
To load as a complete polyline, it is required to select via the "SELECT POLYLINE BUTTON". This button is only enabled when the DXF file includes a valid Polyline.
The Dialog box that opens (as per included Jpg) will allow you to tick the checkbox for "Reverse Polyline" (V1.6.4.4) and then Select the Polyline required.
Once all selected, Press the OK Button to exit the dialog box, and the whole polyline should now be selected.
Selecting on screen will only select or De-select single entilies from within the polyline.

When processed you will then be able to delete all the rough cuts leaving just the finished cut, that should be all you need.

Free (or cheapest) turning CAM?-selectpoly-jpgFree (or cheapest) turning CAM?-selectpoly2-jpg