Hi Terramamba
First off I'm no expert, as I'm new to this chilli growing lark myself, but I have read up quite a bit on the net.
Not sure what type of Naga you have, but it seems most of the very hot chillis require similar care like this below.
'The Bhut Jolokia are extremely hard to grow and therefore not for the novice.
We want you to succeed, therefore please read how to get the best from your seeds very carefully and closely follow the cultivation advice.
Bhut Jolokia requires constant soil temperatures of between 75?F and 90?F for proper germination, optimally 80-85F. In the UK it is best to supply bottom heat with the aid of a propagation mat or propagator. The seed is unlikely to germinate without additional help in an average UK central heated house.
Soil based compost is best and should be fine and free-draining. It must be kept moderately moist, but never being allowed to completely dry out and never allowed to become soggy. If excess moisture is provided the embryo in the seed will rot and they will not germinate.
The Bhut Jolokia can take between 20-35 days to germinate depending on the temperature provided, patience is required. They also require a very long growing period, up to 160 days for full maturity
Sow from Feb onwards in the UK indoors with heat provided and lightly cover with vermiculite if possible to 1/4in depth.
Beware starting too early as the plants require good light levels as seedlings may become leggy.
The seed does not require light during germination; however, once the seeds have germinated you need to provide adequate light for the seedlings. A bright draft free south facing windowsill will suffice to maintain healthy growth.
Beware over-caring for young seedlings and over-watering. Allow the soil surface to dry and remove any excess water from trays to ensure roots do not rot.
If intending to move to a cooler conservatory or greenhouses in early summer gradually acclimatise the plants both to the higher light levels and temperatures.
Please note this variety is not suited to outdoor cultivation in the UK at any stage and will not appreciate unheated glasshouses in early spring until the weather warms.'
Yours may still germinate, so I personally would stick them in the airing cupboard (that's what I did with all mine) until they start to germinate, and then straight away put them onto the windowsill.
Hope that is some help.
Martin