Hi eng.mbashar89,
Did you manage to do what Victor said?
Please load the latest 6.5.2 InstantOS code if you are planning to use it as an instant and once you load the code and it reboots you will see the "Setup-last 4 of the AP" SSID broadcast instead of the "instant" SSID and then you should be able to configure it
If you don't see the "Set me up" SSID, how did you get the GUI? Via the "instant" SSID? According to the datasheet, this is an AP 802.3af-compliant source, so it woudn't need POE+.
About the other:
1 - Generally the AP with higher uptime (the first you turned on) is the VC, but you can set an AP to be the VC via the preferred-master option.
2 - The master AP will always take the VC role.
Please take a look at the following two videos and you will get a basic understanding about Aruba Instant, and also they will answer your third question:
https://www.youtube.com/watch?v=vXiltl8bnek
https://www.youtube.com/watch?v=aS9Q8aZXdZ0
Regards,
Julián