Thanks for the link Katie, can't wait to read it.
Well I hope you're not disappointed when you click on it, then!

Not many words there...
OK, good, I just wanted to clarify how you were doing your interval training. One thing I've learnt regarding losing fat, is that you should do your interval training (also known as HIIT - high intensity interval training) at the
HIGHEST intensity possible! Keep the total workout under 20 minutes, because if you are doing it longer than this, you could've done it with more intensity.
So you are running 4 lampposts, that's great, but are you running them as fast as you can (feeling like you're about to die by the last lamppost)?
For example, lately I've been doing 1 min sprints, 1 min walk, repeat until 20 mins is up. The thing about that is, 1 min is actually a little too long to sustain a high intensity, so I started doing 30 sec sprints, 1 min cooldown. Incredibly intense...
So yeah, make sure you are working at high intensity (although if you do boxing I'm sure you know what that feeling is like)
Also, I am 5'4 as well, so I think something in the low 60kg range is great, but personally I wouldn't go lower than that (losing 10 kgs would put you at 57kg). I used to be 57kg and skinny-fat, and now I'm actually a lot healthier around that low 60kg range. But as the others say - don't focus on the weight - in fact, chuck the scale out if you can bear to do so! Just focus on how your clothes are fitting you, they're the best indicator.