Trendlines Shift on Nonlinear Charts

Trendlines need price & time in order to plot. On a nonlinear chart, time cannot be predicted, so MotiveWave will estimate the endpoint, therefore, the trendlines in this case may shift .

You can plot the endpoint on the previously plotted nonlinear bar or wait until the current bar closes. The endpoint can then be extended, and it should stay stationary at a fixed angle. Trendlines will only be plotted exactly from timeframe to timeframe if the new timeframe has enough data loaded.

What you could do is right click on the chart then select Chart Settings > Display tab, try enabling the Resolve Trend Lines option. Be warned, having this enabled can load quite a bit of data which will increase loading times.