LH Fingering McKikkop "20 Easy..." Exercise 1

I've got a LH fingering challenge on the very first exercise. Oddly I have no such problems with the next two.

In the second bar I'm currently playing: (pitch-string-fret-finger)

a'-4-2-2,
c'-3-o
f'-2-1-1 (so far, so conventional)
a'-4-2-3 (Starts getting weird here . . . )
Slide to... bb'-4-3-3
g'-2-3-2
a'-4-2-1
c'-3'-o

Is there a better way around that? At CD "Fast" tempo, the only difficulty is consistency, which I suppose is the point?

I just received this book and I'm studying this exercice too. I use exactly the same fingering.