problems with labeling contour lines - 2nd try

Hello - I have two problems labeling contour lines in 0.98.3.

First, when I call
clabel, it removes all contours that are not labeled (because the label
doesn’t fit on the section of contour, I presume).

This seems like a bug to me (or a really odd feature).
Easy example:

x,y = meshgrid( linspace(-10,10,50), linspace(-10,10,50) )
z = log(x2 + y2)
cobj = contour(x,y,z)

cobj.clabel()
<a list of 8 text.Text objects>

draw()

Second, when using the new manual labeling of contour labels works (which is pretty neat!), how do I end this feature?

The doc string says: right click, or potentially click both mouse buttons together (which already worries me).

Neither works for me on win32, mpl 0.98.3, TkAgg backend, interactive mode.
Does anybody have a solution?

Thanks, Mark