Strange thumbnails behaviour

People,

I’m trying to make the thumbnail a little big but I have a strange behavior. If I change the value of thumbnail height, the gallery cut the image.

I’ve try every combinations of sizes and nothing happen and just work if the thumb have 80 pixels height.

Someone have a clue about it? I attach a shot in the link of this message.

Thanks

http://wordpress.org/plugins/image-gallery-reloaded/