A lot of the video's are showing the machine in a bonus round. You stated that the video's you watched the machines were spitting out tokens. So when you are playing the machine and the credit meter reaches 50 and you are winning the machine will payout.
This is normal, they are only allowed to show 50 on the credit meter. In credit mode you can load the machine with tokens, till the credit meter reads 50, then they start falling into the payout tray. In cash mode you have to put 3 tokens in every time to spin.
Pushing and holding the button changes the machine between these two modes. If a zero shows in the credit window it is in credit mode. If nothing shows in the credit window, it is in cash mode. The red button you are talking about is the Cash/Credit button.
Anything over 50, on the credit meter, will be payed out if the machine is in credit mode.
