Ignore the opening scene of Last Stand.Let's be honest the reason for that
Is at time Bryan Singer probally only wanted First Class to be seen as prequel to his films but Fox later made it clear they wanted Last Stand In cannon.
Xavier said magneto helped him build cerebro.he never said they Invented Cerebro.Easy way around It.Offscreen during first Class magneto helped Xavier rebuild cerebro protype In mansion.
Yes magneto's helmet Is an error.a possable way around it Is The Shaw helmet eventully was overpowered by Xavier and Magneto bulit a more powerful version and Xavier was surprised by this.
Moira Is a major plothole and Is sign first Class was originally suspose to be prequel to X-Men and X2 only.
The dialogue about past when It comes to hwen Xavier and Magneto first met and Cyclops,storm,and jean as some of my first students Is getting trying to debate.man franchises and TV shows make liberties with what Is said In dialogue.
Beast on TV In X2 was easter eggExpecting them to stay true to maybe 30 seconds of screentime Is silly.
As has been mentioned In this thread nobody Identied them In first Class cerebro sequenze as storm and Cyclops.It's getting to be pointless debate.