Monoslideshow captions

I just bought Monoslideshow and have it working with the Nextgen plugin, but I can’t customise the style of the captions, which was the reason I bought it in the first place. The demo made it look easy but I’m not sure it’s even possible in this Nextgen version. Have I just wasted 25 Euros or can anyone suggest how the caption style can be changed (e.g. position, background and text colour, font style and colour)?