I would have to askl my friend Miguel CHeca, who is a Proffessor of International Private Law in University of Cadiz on that point.
Of course sure that if you are an Andalusian resident ( and from my knowledge on some other regions too) inheritance tax under those or similar circumnstances becomes almost inexistent.
Anyhow as in every tax issue, specifi consideration is needed, specially in INternational forums.
Anyhow I can aks about INheritance Tax Taxation Treaties between Spain and the UK to Miguel. Please let me know if you like the query to be done.