There are two square recesses in the front plastic bumper cover,
but I did not see anything between those and the bumper itself.
Are there supposed to be other parts that would hold a bracket,
such as a captured nuts or inserts to received screws to hold
the license bracket?

I am also interested in know how people dealt with missing
license bracket. I do not insist on all OEM implements but would
like to avoid drilling / tapping the bumper for mounting screws.

Thanks,
Lih-Yen

When I picked up a replacement front bracket at the dealer, they told me that the square mounting plugs always come out after a few years anyway. Then they gave me a couple of complimentary machine screws for tapping into the bumper. The thing's been on there for a year and is as solid as the day I put it in. Plus, it looks just like the original installation.

I got mine at the wrecking yard for 2 bucks. Only way to go.