try to map your movement keys on the Keypad 4, 5, 6 & 8, instead of the arrow.
Alternatively, assign 1 key per strike, so you won't have to press up/down to select your strike.
Note: some keyboards have issue detecting 3 keys pressed at the same time, but if it happened only coz you changed your OS, I'm not 100% sure it's related.
== Mana Games ==
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