both of the H nd F splines have two complete splines in them and it's messing with the Extrude. Select either H or F and in Point mode select one of the non-corner points and do a Select/Select Connected, then delete - you will see there is another spline in there that only uses points on the corners. After that it works fine.
I don't know if this exists in the Lite version, but in R16 you can select the spline and then run the Mesh>Splines>Explode Segments command. That will split the spline into two spline objects. You can then delete one of them and it will work fine.