But I wonder, how I set clock to display on screen?
Glad you like the large battery-meter display that is one of SDM's large-character pages.
In ALT mode, press the right button to browse over 50 displays.
One of the first has a clock (in large characters) at the top.
Simply exit ALT mode to make the clock live.
It displays hours, minutes and seconds in 24hour format.
To toggle display on/off, simply half-press shutter and right button.
You may find this far easier to read than the 'official' build.
The 'official' build only has a tiny battery meter.
Explore the other 50+ pages !
David