I think I have done that...
let's say I have in my referenced dll some 'huge' tables
like:
MyTable(0)=1234
...
MyTable(9876)=19283746
in a class named MyClass in the class initialize event
Of course, I have
Public MyTable(9876) as long 'in a module
Dim asd as MyClass 'just after Option explicit
and at form load event,
Set asd = new MyClass
that will bring you to the class initialize event and your table will be in memory for good.
the lag time is at app start only and table will be in memory as long the app is running.
does it answer your question?