Hi Dave,
I haven't done a lot of research on narrow gauge lines in either Eastern Europe in general or Poland in particular. But what I have found tells me the loss is mine because from what I can tell, there was/is a WHOLE LOT of narrow gauge in the region.
The only completely Polish reference I have is: "Nasze Koleje" by Bogdan Pokropinroh. I think this line ran/runs between Warsaw and Radzymin, a distance of 19 km, and was/is 800mm gauge. The only other thing I feel very sure of is the word "obrotnica" means "turntable". The book was published in Warsaw by WKL.
I've had this book for decades and can't read it. (It was free and needed a home.) I'd be happy to talk with Dave, Ira, anyone else - if they can help unlock this multi-decade mystery.
Please send me email.
Best Regards,
Glenn