Hooray, the spline export is actually useful for something.
Method 1 (coaster uses center of rails):
-from center of rails, change the heartline to the desired value
-make your element
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-go to the professional tab and export spline. Click ??????center of rails?????? and save it. Make sure the element you want to export is the longest spline.
-set the heartline back to center of rails and import the spline back in.
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Method 2 (coaster uses heartlined track):
-If you want to use an in-line twist on heart-lined track, change the heartline value to the opposite sign of the original value. (if you're using a heartline value of 1m, change it to -1m and vice versa)
-make your element
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-go to the professional tab and export spline. Click ??????center of rails??????. Make sure the element you want to export is the longest spline.
-set the heartline back to the original value and import the spline back in.
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Have fun with your El Locos and Banshees.