according to wookiepedia, the length of an hwk is 29 meters:
http://starwars.wikia.com/wiki/HWK-290
if that is the case, the model would be closer to the length of the falcon.
however, that measurement can easily be wrong.
using this image, we can see how wide the walkway is compared to kyle's height.
http://www.jediknight.net/trail/images/15_wk_11.jpg
from this, it looks like the length of the moldy crow is approximately 6~8 times the width of the walkway. if we use kyle's stated height as 1.8 meters ( http://starwars.wikia.com/wiki/Kyle_Katarn
), and bs the math to say that the walkway is about 2 meters wide (honestly didn't pull out a protractor and use trig to find the right width), that puts the modly crow at anywhere from 12~16 meters.
that is well short of the stated 29 meters on wookiepedia, but does put the hwk 290 much closer to scale.
congrats ff!