[Qgis-user] Layer style: Graduated classification not working (2.18)

[Tim Bowden]

Worked fine for QGIS 2.16 but not 2.18: Can't do "graduated"
classification for the style as per the tutorial (http://docs.qgis.org/
testing/en/docs/training_manual/vector_classification/classification.ht
ml#moderate-fa-ratio-classification)

When I pick "graduated", it won't let me pick any field apart
from OGC_FID.  When I use the expression editor to chose another field,
it reverts to blank field once I press OK in the expression dialogue.
 I've tried this with my modified landuse.sqlite file (with new 'area'
field as per tutorial) and with a fresh copy.

Have I done something wrong or is this a fresh bug for 2.18?

Regards,
Tim Bowden