Daniel,
The F28377D is supported on SYS/BIOS 6.37.01.04 with XDCtools 3.25.05.94.
http://downloads.ti.com/dsps/dsps_public_sw/sdo_sb/targetcontent/bios/sysbios/
http://downloads.ti.com/dsps/dsps_public_sw/sdo_sb/targetcontent/rtsc/
In order for you to see this device in TI Resource Explorer, you need to use CCSv5.5 and install a CCS software "patch" update (Help->Check for Updates).
http://e2e.ti.com/support/microcontrollers/c2000/f/171/t/310052.aspx