Export extension fails to run: trying to extend '/FSpot/Menus/Exports', but there isn't any add-in defining this extension point

["Stuart Langridge" <sil kryogenix org>]

I'm trying to compile the example export extension for F-Spot as per http://f-spot.org/Extend_F-Spot, to plug into 0.4.0. After a bit of fighting to work out how you tell gmcs where your "home folder" installed F-Spot is (answer: set PKG_CONFIG_PATH to point to the pkgconfig folder in your local installation[1]), it compiles fine. However, when I try running my home-dir F-Spot with the new addin in place, I get this error:

WARNING: The add-in 'FSpot.__dumpFiles,0.0.0.0' is trying to extend '/FSpot/Menus/Exports', but there isn't any add-in defining this extension point

and my extension isn't enabled. I'm not sure what I might be doing wrong at this point...

sil

[1] this could usefully go on the Extend_F-Spot wiki page, which I'm happy to do if someone gives me an account

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