New answers tagged profile
..and also make sure you have chosen 'Selected polyline' and not 'temporary polyline' within the profile tab of the Profile tool (the cursor will change to a hand from a cross)
The file can be opened in Notepad, which can then be saved as a .csv and imported via mmqgis, so all fine here now!
I had the same problem and tried James S' solution, but couldn't get the GDAL to work with Fiona. Then I discovered the SAGA algorithm "Cross Profiles" in QGIS 2.4, and got exactly the result I wanted and that I presume you are looking for too (see below).
It is handled by an esri geoprocessing service, which it is recommended that you update from the old service. The details page mentions plenty of good reference information.
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