OK, so after searching this forum, I finally worked out to put my number and not the $EXTEN in the dial plan for the geographic number.
Anyway I notice from using
http://wap.e164.org that the lookup chooses landline numbers over 0800 numbers (in UK). Seems to me 0800 numbers should be boosted to the top even if you specify a landline number for your own number. Leaving my number blank on the webpage does this, but I can't leave the field blank in VoXaLot. Anyone know how to work round this?