El problema es donde obtienes ese night rating
France, Portugal, UK, or within Spain itself (I believe it's done during IR training, but I'm not sure).
no existe por parte la DGAC esa cultura del vuelo VFR nocturno
As I understand it, the issue is not so much with the DGAC, as they have approved night VFR--it's in the AIP and everything, but with AENA who are not willing to pay for their controllers to get the Night VFR qualification, and of course according to the AIP (IIRC) you can only fly NVFR from approved
controlled airports... of which there are none
The Netherlands have a similar problem, btw, so you're not alone.