Winterbottom describes Smith as a 'shadowy figure', giving no biographical
details other than he was described, on appointment following the death of Governor
Wood, as Colonel of the Fourth Regiment of Horse. In the German Parish Register
under 1787 is an entry for the confirmations of "Miss Kitty Cooke &
Miss Penelope-Ann Cooke, daughters to the Lady of his excellency Edward Smyth
Esq Governour in Chief of this Isle" so it would appear he married a widow
Mrs Cooke (there is in the IGI, a marriage between an Edward Smyth and Penelope
Cooke on 24 July 1786 at St George's Hanover Sq, Westminster, that would fit).
Appointed by Whitehall to uphold the English influence - John Murray describes him as "a total stranger to the manners, laws, and customs of the Isle of Man" before bitterly criticizing the hasty (and probably unconstitutional) passage of the 1777 reform acts.
Roper (a strong partisan of the Duke of Atholl's cause) goes even further: in 1825
This gentleman, from the moment of his appointment, seems to have been haunted by a spirit of legislation ; and being surrounded by persons anxious for the establishment of their own encroachments, and the consequence deterioration of the Dukes rights and being himself entirely ignorant of every thing relating to the Island, he was led immediately to concur in certain Acts of Tynwald, and flattered into doing so, by those who had cunning enough to persuade him he was himself capable of drawing those Acts when, in fact he was only a tool in the hands of his advisers.
and later in discussing the Act which removed the appellate status of the Keys placing more power in the hands of the Governor
Governor Smith was led to conceive himself a Judge as well as a Legislator, and that the Keys indulged his folly, and purchased the abolition of the Grand Enquest, by relinquishing to the Governor the appellate jurisdiction in jury cases. Ill calculated as the Keys are for the trust reposed in them as an Appellate Court, Governor Smith thinking himself better qualified in his own person alone, to correct the errors of a Jury, and thereby improve that mode of trial, evinces a degree of vanity, pride, and arrogance, and in an Englishman indicates such ignorance of the principles of the British Constitution as to disqualify him for his situation
Smith would appear to have been away from the Island for much of the time, leaving day-to-day control in the hands of the Lieutenant Governor (Dawson and later Shaw). The two major acts at the start of his governorship would appear to be the total.
D. Winterbottom Governors of the Isle of Man since 1765 Douglas: Manx National Heritage 1999 (ISBN 09524019-5-9)