Discussion: OCAD mass cutting of contour lines?

I'm a beginner mapper using OCAD 8 and the latest beta version of Ghettocad for realtime GPS tracking on my IPhone. I've been using LIDAR data for basemapping and QuikGrid for contour generation which all works fine.

The challenge I have is that I have to manually cut the contours one at a time which are out of boundries of my selected map area. This is very time consuming, so the question is if it is a way to cut multiple contours in one operation. In other words mass cutting with OCAD 8. I keep the 1 meter contours for the field checking which makes the manual cutting job even harder.

Using one of the area symbols (I generally use the lake symbol), outline the region that you want to keep. Then under Extras select Partial Map and click on Use Selected Region. It will save the selected area to a new file.

one thing I do is to use a different symbol (color change or dashed) for the odd and even contours . That makes wholesale hiding/elimination of them easier when you want to get rid of one of the two sets.

That sounds like a great solution.
Thanks.