I found some rule -
 
	in a small map, all chairlifts are working good.
 
	 
 
	this map is 253 x 253 sized huge map,
 
	and as shown in this screenshot I roughly made chairlift without saved track,
 
	they are working in half area, and not working half area. (green sign is working, red sign is not working)
 
	 
 
	and, I tried this- uninstall openrct, and play same map in original rct2.
 
	yeah. all chairlift are working good.
 
	 
 
	if this save file is not working,
 
	would you mind make a huge scenario map and test?
 
	 
 
	I really appreciate your attention. thanks!
 
chairlift fail.sv6