Please help : Replaced screen "5158N FPC-1 06WW 1210" with a "5158N FPC-1 06WW 1225". Is this a big difference? I thought being a 5158N FPC-1 was enough.

Then after setting it up, I don't see anything in screen. I know device is on, because makes noise when unplugging it, and I can navigate folders when plugged to a computer. And left out a little piece (magnet double metal square piece, of 1 cm approx) is out of its place. Don't know where it goes now .... Please could you help me in any way? thanks in advance!

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