First, what you posted is not a keyboard hook. You're just peeking at the state of certain keys.
Second, what's with the Timer?? You may be calling this "key peek" code 10 times a second, but that's no guarantee you're going to see a key state change.
I'd tell you how to fix this, but it's not fixable. Seriously, this approach will never work. You have to scrap this and use a REAL keyboard hook. Only then will you gain the ability to "eat" the keystrokes so applications can't see them.
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