question about connections/immigration at ORD

I am hoping that the well traveled here can help me out. I am booking a RT for my sister-in-law from NRT to NYC via ORD. This is C if it matters. What kind of connection time should I build in for clearing immigration and making sure the bags make it to her flight. She is flying NH over water and UA to and fro ORD-NYC. I have options for LGA and EWR. We live on the flight path of LGA, but that is the tighter connection and in economy. The EWR has business options. She is *G as well.

I guess my two questions are:
1) what is the realistic connection time that I should build into her award?
2) will there be any issues with number of baggage onto UA (thinking no because of *G and booked a C award ticket)?

Thanks!

 

If I was you I would make sure I had 2 hours at a minimum at ORD due to weather at ORD (Snow in Winters and Thunderstorms in Summer).

If it's one ticket with UA and NH then the baggage will be checked all the way through to Newark however your sister-in-law will have to claim it and recheck the baggage in Chicago.

 

Inbound to the USA also requires the T5 transfer which is annoying and adds time. If she's going to enter via the "visitor" line figure on the extra time that takes as well.