Before I begin, a gentle piece of advice:
Use the below for you education only, and not for any personal gains (except maybe to inflate your own ego!)
Anyways what-ever you do, I am not responsible for the outcomes (viz. if your deeds get you caught/banned online) !
Well here goes –
1. Get Firefox! (yes, only Firefox is supported in the current solution!);
2. Install tamper-data add-on – https://addons.mozilla.org/en-US/firefox/addon/tamper-data/
3. Start Tamper-Data from Firefox –
Tools –> Tamper-data
4. Try to open a new session in Firefox (or only the desired flash URL in your browser or you will have a hell of a time tackling submit requests in Tamper!)
5. Fire up your flash game. (this can be done after the above step too)
6. Play and loose, or die or what-ever, just finish the DARN thing!
7. Wait till you reach the high-score window/dialog in the game;
8. Hold it, don’t submit yet!
9. Ok, now just start your Tamper process by choosing start Tamper in Tamper window.
10. Now click submit, and wait till Tamper data takes over.
11. The dialog appears asking you to tamper the current server post values;
12. Pay attention now!
a. Remember, first Un-select the checkbox of continue tampering;
b. Then choose the Tamper button.
13. In the new ‘Tamper Popup’ window which opens, check the parameters in the right panel;
14. You will find the parameters user name (whatever you types as user name) and the ‘not so high’ score you managed to get!
15. Manipulate both, and select submit/ok.
Check your score now in high scores!