GenoProSupport answer was that in the future, GenoPro will support time and then the conversion will be more accurate. I suggested that GenoPro will use a checkbox for that matter. It will be easier to convert the dates.
Gregorian calendar
English
Mr.A: born 31 Dec 2005 died 1 Jan 2006
Mr.B: born 3 Oct 2005 died 4 Oct 2005
16b RESULT SITUATION after 1st CONVERSION (to Hebrew calendar)
Hebrew calendar
Hebrew (English)
Mr.A: born 1 Tevet 5766 died 2 Tevet 5766
Mr.B: born 1 Tishrei 5766 died 2 Tishrei 5766
CORRECT RESULT SITUATION after CONVERSION from (GS) to Hebrew calendar
Mr.A: born 30 Kislev 5766 died 1 Tevet 5766
Mr.B: born 29 Elul 5766 died 1 Tishrei 5766
16b RESULT SITUATION after 2nd CONVERSION (to Gregorian calendar)
CORRECT RESULT SITUATION after CONVERSION from Hebrew calendar to Gregorian calendar