When I used QGIS 1.8, I was able to transform polyline layers to polygon layers with the Polygonizer plugin.  In QGIS 2.2, this function has been subsumed into the Processing toolbox.  Unfortunately, it doesn't seem to work.  I see that this problem has come up before (http://gis.stackexchange.com/questions/85452/make-a-polygon-from-intersecting-lines-in-qgis-using-polygonize-or-similar) but hasn't been resolved.

Here's my polyline layer:

![input](http://www.blackthornecology.ie/wp-content/uploads/2014/05/input.png)

And here's what I get when I run the polygonizer function:

![output](http://www.blackthornecology.ie/wp-content/uploads/2014/05/output.png)

Only a fraction of the closed shapes have been successfully closed by the polygonize function.

Can anyone advise on how I might get this to work correctly?  As I said, I was able to do this sort of thing with the old Polygonizer plugin, using the slow/old methodology.  That doesn't seem to be implemented in the new function in QGIS 2.2.  Is there somewhere else I could find it? 

Thanks in advance!

ETA: Running on Windows 7.  Installed via the standalone installer on the main QGIS webpage.

ETA2:  I installed QGIS 1.8 again and was able to produce this with the old Polygonizer plugin (with the output from the QGIS 2.2 processing function on top).  This was produced using the "Old method" in the Polygonizer plugin.  It took a long time but it worked much better.  The "New method" in the Polygonizer plugin produced the same polygons as QGIS 2.2.  So it appears that only the old plugin "New method" has been carried forward into QGIS 2.2?

![old polygonizer output](http://www.blackthornecology.ie/wp-content/uploads/2014/05/old-plugin-output.png)