I've recently started playing with SubSonic on a new project.  My first few attempts at generating code failed.  The files were being generated, but they contained no code.  I'm sure it states it clearly somewhere but I was in one of my moods where "By golly, I'm not reading the stinking documentation, I'm figuring this out myself."  Well after an hour or so of this, I finally discovered, SubSonic really likes primary keys on the tables it's generating code for.    I had a few tables that didn't have primary keys (I know, smack me now), anyway's I throw those keys on and all is well. 

I'm really liking SubSonic and I tend to agree with Rob more than Jeff in the recent debate (makes for a good read).