Hello,
I am not a modeller, but have recently been researching CDR station layouts. I’m working on Stranorlar and getting information for Strabane.
I might be able to help with Strabane. I have spent my life working with maps and plans in the UK. Now I’m finding out about Irish coverage, or lack of.
OSi have the old 1:2500 (25") accessible online. As you have noticed, the S&L is later than the plan surveys. Some coverage exists with the 1:10560 (6") maps, but track layouts are very generalised.
PRONI - for some reason - do not have the 25" series online.
Fortunately, there is a blog that has some coverage:
http://oldstrabane.blogspot.com/2010/09/1905-ordnance-survey.html
It is possible to download the plan shown without the help of Google Earth.
The reason you are seeing blanks is because (I think) of the way PRONI presents the 6" coverage. In other words, the blanks are because no sheets were available for that series. You have to switch between the different layers. By using screenshots, I was able to combine the sheet with the FVR junction and later coverage post conversion to narrow gauge.
You should have Patterson’s books and the later revisions by Joe Begley & Steve Flanders.
A previous post on this website included some additional information. Unfortunately, I can’t remember the posting. I can’t find a way of posting images here....found it.
One of the sketches was done by WJK Davies author of many narrow gauge books. The sketch looks post-1955, after closure of the line to Londonderry.
Hope this is of some help.