you have to do it for each part once. SE will then continue
to update it on every save.
After you're through with all the parts you have to do the
same for the 'container' asm. SE will neither update
it on save nor won't you forced to save after you've updated
the properties. When the only action on an asm was to update
the physical props SAVE that file afterwards!
Draft:
=====
When your draft of a part shows a thin gray frame then
this is an alert that the underlying part is out-of-date.
Thick gray corners will indicate an Asm and one of its
parts is out of date. Use Tools --> Drawing View Tracker
to check which parts/(sub)asm have to be updated
