QNX: Qt Example Clocks only shows background color after startup

One potential customer using evaluation version encountered one issue on Qnx 6.6 & TI J6 board.
The version of Screen library that they used before is screen-jacinto6eco-2016-04-02-spectre -660-b78, and Qt 5.9.8 worked well.
But after they upgraded the Screen lib’s version to jacinto6ECO - 2018-04-27 - spectre - 660 - B376 because of some new features, the Qt demos and their Qt program worked abnormally.
The clock demo only displayed the background. And their own projects showed normal when the opening sequence was animated, but when they got to the main screen, there's only the background.
The Qt was built from source.