The MegaRAID Storage Manager application you specify the IP Address not the DSS V7. And yes you want to use the GUI management NIC. The issue your having is that the MSM is picky!! Not the DSS V7. So what you need to do is find out the build your using with the DSS V7 and match as close as possible to the firmware date of the controller then find the MSM that matches those dates. This is the issue as the MSM is very picky about that and can cause the issues your having.