Presta 1.7.1.1 Image Slider

[nbexiga]

it's regarding the "Prestashop Image Slider" , i have some images configured there with link's etc.. , the photos that i use there are good quality and resolution.
but i notice when i see the slider working it does not adjust the image to the slider box.. it seems that cut off the image in the bottom.. :(
i want to know if you can give me a tip where i can change this.
one other thing is if i resize the Chrome window to a smaller size i can see all of the image, but in full size not.
i atached an example of what i am saying.

please help me.
many thanks