Yours disappeared because it was too big. If you shrink it it will be fine. Again the rule of thumb in signature sizes:
Look at the HEIGHT of your browser (visible window). Divide that by 4 and if your signature occupies more than 1/4th of that window it is too big.
Take advantage of colors, smaller fonts, put more information in one line. You can get a lot more in this way. Remember that tickers occupy a lot of screen. A ticker and a pikistrip will get you easily over the limit.
HTH