Remapping the keys will (normally) fix the keyboard issues because it's a hardware issue. The computer can't detect the inputs because of the conflicting "switches" in the keyboard itself; the problem isn't caused by the actual computer as it were.
Example inputs using my keyboard:
Shift + z (+ left+up / down); works
Shift + z + right (+ up / down); does not work properly
z + x + left (+ up / down); works
z + x + right (+ up / down); works
The first set has a conflict in it which prevents the second set of input from working properly. The second set, while it uses the same number of keys does not have a conflict because different switches are used, and thus the input goes through.
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