Capital Loss on an EIS share

[UncleEbenezer]

One of my crowdfunding flutters[1] has gone belly-up. The liquidator's report confirms there's nothing for shareholders. I received EIS relief on it in 2014-15. Since I'm at no risk of capital gains tax in my lifetime, I want to offset it against income tax, and carry that back to include in my 2016-7 tax return.

I've been doing battle with the online form (specifically the CGT worksheet), and it doesn't seem to deal with EIS as such. I entered in text the amounts (£400 gross, £120 EIS relief received, £280 net loss), but it's not clear which figure I should use for the amount invested. I entered £280, but then I find EIS mentioned in a later page, so I think I should have entered £400 in the worksheet and the EIS relief in the later page. Is this correct?

Also, I have to enter a notional disposal date to claim nil value. I could use the date of the liquidator's report, but that brings the complication of being a couple of months short of the EIS qualifying period (3 years from November 2014). Other dates I could use are the notional EIS qualifying date, or today, but none of them has much of a basis. Any advice?