With the above out of the way, I wade in...
Pardon my ameratzus, but can we please start from the beginning? (Maybe we need to learn a little Jewish and world history...
)
Who/what gave the V4A the halachic "koach" to make takanos?
Was it the fact that they were representative of the united kehilos under its purview?
The de facto acceptance by the relevant members and/or rabbanim of the aforementioned kehillos?
The governmental sanction of the semi-autonomous' nature of the Jewish kehillos under the vaad?
How was the koach of the takanos of the V4A different from the koach of the takanos of, say, Rabbeinu Gershon, or Hillel Hazaken, or Ezra, or Shlomo Hamelech?
How does the split of Lita into its own independent Vaad affect the preexisting takanos of the vaad?
What/why halachic ramifications were there from the end of govt sanction of the vaad (due to non-payment of taxes, I believe), and the subsequent end of the (twice?) yearly meetings of the vaad and what happened with previously enacted takanos?
Shortly after this, the area that had been previously under the vaad was affected by the partition of Poland, and the disappearance of Poland from the Map. What halachic ramifications did this have on preexisting takanos of the V4A?
During the period of operation of the V4A, if a resident of a member kehila traveled to another area, say, Italy, France, EY..., was he still obligated by the takanos of the V4A? (m'dina degemara... chumri makom she yatza misham)
When the V4A ceased to function, were the members of the constituent kehilos still obligated by its takanos?
After the end of the V4A, if someone who moved to a Kehilla which was still keeping the takanos, was he obligated by the the takanos? (makom shehalach lesham...)