That's what I use also so I'm afraid I can't help much-
"3. What do the colors mean on Time & Sales? The colors signify the following:
Green = trade occurred on the Ask. Red = trade occurred on the Bid. Cyan = trade did not occur on the Bid or Ask. Yellow = trade broke either high or low for the day.
4. What do A, B and U mean on the Ticker? A-The sale occurred on the Ask. B-The sale occurred on the Bid. U-Undetermined, The sale did not occur on the Bid or Ask."