I received a reply on my bug report. They said that they are aware of the problem and it should be repaired by the next update (whenever that may be). They also said about what was suggested here before about how to do it in the meantime and that it wasn't as straightforward as my way had been. And they were right about that! I did make a test route and kinda got the hang of it, but adding on to a track that already has slope to it just doesn't seem to work for me. So, its been fun laying track and manually lifting the splines one at a time and measuring the slope and moving the splines and measuring the slope and moving the spline..................sigh.
