a few words ... there is an all VSL application license which works for all products, so if you have say from solo strings only the standard library (like cgernaey) and are loading something from the extended library a start is used (from the all application license).
all Vienna Instruments Collections have demo mode #2 licenses for trying out the extended libraries (date license 30 days 30 starts) which are related to a certain extended library (again, say solo strings).
for the Vienna Suite there is also a demo license available. earlier versions used 1 start per plugin, the latest versions even only 1 for the whole suite. closing a project and re-opening it will also use a start.
if no more starts from the date license are available and you still have starts on your all application license left, those are now used up.
actually during AU validation (or VST check) only one start should be eaten - if you notice more please check your system (eg. permissions), re-iterated validating would also use a start with every iteration.
every other behaviour is not intended, but the succesion of events should be considered (as side effects from failed validations or loaded extended content should be).
however i have asked our mac support to double check if some failure happens with 10.4.11
hth, christian