Chris,

Attached is an example of how you could build such a staircase using boxes and triangles. You can find the triangle on the 3D Models page. Make sure to rotate it 90 degerees while importing it.

You can make the four irregular shaped treads by combining a box and a triangle. Use the Group command to make a single shape of it, which you can then copy and mirror to obtain the correct model.

Stringers can be made by drawing a wall of the desired dimension (in a separate instance of SH3D), then using Export and Import, giving it the correct rotation during importing. See the tutorials here or use the help pages.

Hans

http://www.mediafire.com/?bzevi7quhhk1ljj