Hi Greg
1) No. You can not Import MIBs
2) If you want to Monitor more ports on your device you Need to add it to the Critical Network Adapters Group
http://blogs.technet.com/b/momteam/archive/2011/09/20/what-gets-monitored-with-system-center-operations-manager-2012-network-monitoring.aspx
Critical Network Adapters Group
This group can be updated through the Operations Manager console under authoring. You can add any of the interfaces to this group and the monitoring will be enabled. If the interface connected to your web server isn’t monitored then adding the
interface to this group will give you alerts on problems with the interface connected to the web Server.
3) If you have scheduled your Network discovery it will stay in "pending". If you had selected Manual discovery it would stay 2Idle"
Cheers,
Stefan
Blog: http://blog.scomfaq.ch