Hi i bought Bioforge today , and when i start it i have a big black bar downside the screen
Iam using a Nvida gforce gtx560 ti card
can anybody help me?

Unless your screen and resolution is the same shape as the 1995 monitors you're going to have black bars at the bottom

In case anyone else comes here for a solution like I did, the answer is to edit dosboxBIO.conf in a text editor and set aspect=true under the [render] section.

There should NOT be a black bar at the bottom, the game should fill the height of your screen in a 4:3 aspect ratio. Bioforge runs at 320x200, but was meant to be displayed at 320x240; for some reason, the default GOG settings force the original resolution, which results in a vertically squished image and the black bar at the bottom. You can see the difference in the planet at the beginning of the cutscene when launching the game: it'll be too wide at native resolution but appear perfectly round once it's stretched to 4:3.