Exploded View / Exploded Line Sketch Conflict in 2004

I've just opened an assembly drawing (originally created in SolodWorks
2003, SP5.1) in SolidWorks 2004, SP2.1 and have encountered the
following problem:

Although the Exploded View definitions and Exploded Line sketch
entities were error-free in 2003, the converted assembly and the
drawing did not behave properly.

One of the explode steps that moved a group of 4 instances of a single
type of screw got messed up. Two of the screws were shifted to a
different distance.

I attempted to edit the Explode step and it made NO difference. I
deleted the explode step and the four screws remained exploded.

It wasn't until I edited the Explode Line sketch to delete EVERY line
associated with the screws that I was able to redefine the Explode
step and then recreate the Explode Line sketch entities.

In the case of this example, the "error" was rather easy to notice,
since the assembly is just a small number of components. What concerns
me is the potential for similar Explode View/Line corruption to occur
with other more complex assemblies in which the misalignments could go
unnoticed.

In any event the time needed to rework a previously completed assembly
was frustrating.

Have others seen similar regressions?

Per O. Hoel