[izrafel]

Well there is no problem (fixed it), just wanted to share the info, maybe someone, after reading this, will not loose 3 hours of testing and googling, why the hell , when a color is selected, and used , for example to bucket fill, the color comes out different, or why some features/tools,sometimes work, and sometimes not . it turns out that, when the image is opened, the image mode is set to indexed, which allows very few colors for editions you can actually pick (i believe that it lets you use only colors that are present in the image, to begin with, or their shades).
when you open to edit an image, just select image -> mode-> rgb, and you will be able to do what ever you want with that image
P.S
it would be nice, to get a alert box that that color can not be used, when a situation like this come around .... especially when e newbie in image editing, like me, pick up an app like gimp .