In the 3300 MXE you may need to also change the IP networking to reflect the new address of the controller.
If you have Operator consoles you will definately need to do this otherwise they will have problems connecting to the MXE controller.
With the NuPoint you will need to login either with SSH or a local screen connected and login with admin to the text based menu, select "configure this server", change its IP settings and reboot. Also in the NuPoint you will need to go in the offline menu and the line group (s) and tell the Nupoint the new IP address of the MXE so it knows where to register its IP ports to.
Similar with the MBG you will need to "configure this server"
Plus you will need to change the ICP setttings, again so the MBG knows where the MXE is.
Not sure about Oaisys but i would imagine changing the IP of the windows server and also somewhere in the management studio there will be an entry that tells tge Oaisys where the MBG is for voice taps, i think as well if you are changing IP addresses you will need to accept a new certificate from the Oaisys.
I have probably missed something,good luck.