How to assign a footprint to a component from DXF in ultiboard

[gunz_drawn]

Hi

I just simulated a couple of circuits with tubes using multisim...when transferring to ultiboard i realized they dont have any footprints ...So i exported a few footprints from eagle to Dxf (pls dont tell me to work on eagle cause i've many a times come out tearing my hair off trying to find a component in their database) but i'm finding it hard to assign it to the model...Can anyone please give me the procedure to do this..

-thx