I have more info now. Last night my account only showed the NAV drop
with no updates to shares held and overall value. (I don't look at
this thing every day). My 401k site is fully updated this morning.

As I compare Thursday 5/4 with Friday 5/5, I see that I have higher
shares at the lower value per share. Overall account value slightly
higher. Kinda like what happens on a stock split.

Their website shows both dividend and capital gains action on 5/5/06.