i have an infrant as well, i don't think it works to have the library on it....i would post on the adobe forum, you will probably get a better answer there....
That has been my experience. I can't build a library from the files that reside on my Buffalo Terastation NAS.
I don't think anyone has major-league DAM thing perfected yet - not iView (aka Mirosoft), not Adobe, not Apple. We are all buying software that hasn't tackled some serious integrity and scaling issues in a robust manner.