Unfortunately the reason is as plain as it gets and very simple: there was no supporting budget for doing the Spanish voice recordings, which is a real pity. A game like

requires a significant voice over budget, and the deals which allowed us to get it distributed in Spain didn't leave any room for that. I'm already glad that we managed to get the Spanish translation out - the Spanish PC market has been hit very heavily during the crisis of the last couple of years, and it has become harder for companies like us to make Spanish versions of our games. I hope that will soon change.