Are you saying there are NO non-random girls that show up, or just none of some particular non-random girls that never show? If it's the latter, I cut and pasted all the girlsx. files to a folder outside WM folder for safekeeping, and *only* kept the ones i wanted to see. Now I see those girls all the time.
Also, the fastest way to run through lots of options is make the pregnancy likelihood 90 percent, shorten the preg timeframe to like 3 weeks with 1 week off for recovery, then put all the girls you get into Whore mode or "Have Sex" in the porn studio. They breed like bunnies and you get more variety of both random and real. You can also set qualities like Obedience and libido way high. (I edit the files directly in notepad now, and when i get a combo I like and gets me results, I copy and paste it to others.)
I can try attaching a file you can try. Are there a few girls for whom you already have the pics and girls files? I can try tweaking them for you.