[4] After Jacoba Araba died during childbirth in 1848, Derx fathered a son and a daughter with another, unknown woman while on the Gold Coast.

[1] According to historian Larry Yarak, Derx was less fortunate in the trading business than his boss, governor Van der Eb, which tempted him to compensate his meagre salary by other means; he was frequently accused by the local rulers of Elmina of abusing his position of fiscal by demanding high fines.

Eventually the local rulers of Elmina issued a petition of grievances about Derx' conduct to governor Van der Eb, but it is unsure what consequences this had.

[5] Derx apparently left the Gold Coast in the late 1840s and married Anna Frederika Lamslag in the Netherlands, with whom he had three sons and three daughters.

[1] The Dutch government decided in 1855 to resume the recruitment of soldiers for the Royal Netherlands East Indies Army on the Gold Coast, and appointed Derx as the commissioner in charge.