I've had a brief look into the Randwick generator duggie engine and some of the background.
I don't think it has any connection with these Star engines, except as someone suggested
it may have involved putting a generator engine back into motorcycle use.
The Randwick engine involves the Australian Navy and a Catholic priest !
The Navy was intensely interested in the use of radio for ships, well prior to WW1.
And a Catholic Priest by the name of Archibald Shaw was greatly interested in radio prior to WW1,
experimenting and manufacturing radios in a factory in his backyard in Randwick.
Along with assembling a radio mast there, all of 240 ft tall.
I found this text, which summarizes the gist of it.
Note the mention of dynamo machinery, which I think refers to the Douglas engined (sorta) generator sets we are interested in.
The address is possibly No 4 Dutruc St in Randwick, quite a large house. There is mention of leasing further land from the Church,
without specifying quite where or what this was.
"During a great part of the war the export of wireless gear from Great Britain to Australia was necessarily suspended, and the Australia was forced to rely entirely upon local factories for the provision of these delicate instruments. The Williamstown workshops, established in 1912, proved inadequate, but the gap was very satisfactorily filled by Father Shaw’s wireless telegraphy workshops at Randwick near Sydney. The value of this service on the part of an institution which was already involved in great financial difficulties can hardly be exaggerated ; the number of ships and lives saved by its means will never be known.
The Naval Board in August, 1916, took over Father Shaw's workshops, utilising them not only for the manufacture and repair of wireless apparatus and machinery, but for making, for other Commonwealth departments, dynamo-electric machinery, electrical apparatus, etc.,of which supplies were then almost unobtainable.
https://historyandheritage.cityofparramatta.nsw.gov.au/blog/2014/08/04/world-war-one-the-home-front-radio-telegraphy-in-australia-1914-1818And
https://www.douglasmotorcycles.net/index.php?topic=2218.0There was also a large Navy Stores Depot just down the road in Avoca St Randwick, out behind Coogee,
Its still operational, although now called Randwick Barracks, and most of the Navy stores are demolished and slated for housing development.
Quite how this all ties together I know not, it would be interesting to know the details of who put the generator sets together.
I'm sure it would be in Navy Records - somewhere ?