As usual for ViewForum burnt CDROMs, the Endianness switches from Little Endian
to Big Endian, and then back to Little Endian within an 'Explicit VR' 
private DICOM Sequence (the length of which is *not* 0xffffffff).
The heuristics to guess the endianness looking at the 'delimitors' works.
There are a lot a 'Private Sequences'.
Bad luck for us : there are Implicit VR, we cannot guess it's a Sequence...
We have to backtrack when an Item Starter is found 'out of' any SQItem.