Why [OROM] Intel Boot Agent GE -> CL ?

I’ve sucessfully modified & flashed Z87-plus rom wiht latest drivers and microcodes
While updating drivers, UBU switched the “Intel Boot Agent” from GE to CL and “Intel PRO/1000” to “Intel Gigabit” UNDI. It seems not to cause problems, but why?
UBU has also newer version of same drivers


Another question: The mainboard has a "Asmedia 106x SATA" additional Controller. 4) Other SATA Controller is empty in UBU, means this that EFI has no drivrs for it and cant boot from devices attahed there?