Solved.

For anyone with same problem, the issue was with wrong camera settings. HighSpeedMode must be turned off and than it works ok. Additionally, to turn this flag off, one must set exposure under 100ms first (I got that info from ZWO directly, because I could not change the flag). So to sum up, this is the fix:

indi_setprop "ZWO CCD ASI120MC-S.CCD_EXPOSURE.CCD_EXPOSURE_VALUE=0.05"
 indi_setprop "ZWO CCD ASI120MC-S.CCD_CONTROLS.HighSpeedMode=0"


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