NextGen Gallery working perfectly but problem with flash stuff in page

Hi.. i have instaled the next gen gallery.. it works ok!

I have a video in my sidebar (flash player) addes with the TEXT widget -…. but when i click on a thumnail of a picture in the gallery all the screen goes dark and the picture enlarges.. but the VIDEO in the sidebar stays OVER the dark layer produced by the gallery..

any ideas how to fix this ?

thank you!