Oh dear - those tracks are rather crappy. Looks like a bit of a problem with the mould.
Didn't see any negative reviews before I bought mine so it may just be a one off
With the skirts on you can't see the top run so chould be possible to cut the good links off the top and graft them into the lower run if there enough to go around
Track - there are aftermarket links available in early, mid and late specs
For roughly same cost you could get a
Revell and rob the tracks
Or
There is always scratchbuild your own set......