Yes, I tried this in a past and got an error complaining that the module
state had been sealed (or something to that effect).
I don't really want to place all handles to instances of ModB in ModA's
instance state-- only those instances that have been appropriately
configured.
I think a workaround for this problem is to create a non-meta module
config in ModA that 'stores' the handles (plus additional information sent
by ModB1's instance$static$init). In ModA's Module_Startup I will memcpy
this stored information into its module state.