Bread-Bakers v100.n009.4

I recently acquired a 2-pound Zo.  All of my favorite machine recipes are 
for either 1- or 1 1/2-pound loaves.  I've tried doubling the 1-pound 
recipes a couple of times with varying and less than optimal results (one 
recipe was way too dry and the other was mush).  Can anyone give me a clue 
on how to adapt the recipes I have to 2-pounds?  Most of them are in the 
Bread Machine Magic book.  If there is no good rule of thumb, I may just go 
back to all bread-by-hand, although I do not have the luxury of that much 
time on my hands.
Thanks to anyone who can help!