The Condong sugar tramway routes are on the following three maps.
Northern area from the Cudgen 1974 map. https://drive.google.com/file/d/0ByB-ppGeDyvwaDg4R0VHNFlFLWs/edit
I marked the Cudgen Public School and the present day Crescent Street which was the main road north to the Tweed River up to about the mid-1980s. The approx site of the Cudgen sugar mill is also marked although the map does not show a tramway to the former depot there. The Cudgen Public School today is at the same location as marked on the 1942 topographical map. The mineral sands area is also marked on the original 1974 map along the coast.
Condong Sugar Mill and lines to the east from the Murwillumbah 1976 map https://drive.google.com/file/d/0ByB-ppGeDyvwSWtSTTNuaGNJZmc/edit
Condong Sugar Mill lines to the north from the Murwillumbah 1976 map https://drive.google.com/file/d/0ByB-ppGeDyvwSnJLLUNMTjkxOUk/edit
Unfortunately there is a horizontal sliver of a gap between the two Murwillumbah 1976 map scans although the river allows clues to determine the locations. The portion of tramway missing is main truck line without any branch lines.
The Condong sugar tramway crossed the Pacific Highway at three places; (1) Condong Mill (2) Cudgen Mill line to the Chinderah wharf before the truck line was built directly to the mill late 1950s and (3) the line to Dodds Island as shown on the Cudgen 1974 map where the Pacific Highway is known locally as Oak Ave 28°15'16.05"S 153°31'41.06"E. Melaleuca Station Memorial Gardens and Crematorium is just south of that former tramway highway crossing site. Before it became a crematorium, Melaleuca Station was a tourist venture including static Melbourne suburban carriages and operating Marian Mill’s 0-6-2T Perry 2601.51.1 of 1951. The junction of the new Pacific Motorway and the former Pacific Highway (The Tweed Valley Way) route to Murwillumbah is also in the general area where the tramway crossed the Pacific Highway.
The reference to the line crossing the Pacific Highway in that area was in LRRSA yahoogroup message 7459 Re Harwood sugar mill tramway by Barry Campbell Aug 23, 2014;
(quote) According to what I have read (Principally the article in the ARHS Bulletin of June 1976) there was a line from the old Cudgen Mill to a wharf at Chinderah which was made redundant by a link line from Tumbulgum to Cudgen built in the late 1950s. My grandfather moved to Fingal 1961 or 62 and we made the trip up from Lismore regularly for weekends until 1966 and I don’t remember the wharf line crossing the highway. Otherwise, the Pacific Highway crossed the Condong system twice (sort of). Once at the mill where both 610mm and standard gauge crossed the highway and entered the mill. The second place was in Oak Avenue where the private line belonging to either Mr Byrne or Mr Brinsmead crossed on its way to join the main system. I found remains of this line in 1986 but I can’t see them now as I drive past. This line went to Dodds Island (Not Stotts Island as the 1976 article states) and the bridge still exists. In 1986 it even still had some tram line on it. (end quote)
Maps from the Murwillumbah branch of the Richmond Tweed Regional Library. I scanned as A3 and merged.