I am using a very large base board and I am trying to adjust the terrain below an inclined track but the "Adjust terrain" will not work. It works if I use a smaller base board.

I have another problem with editing the terrain of the baseboard , the response time to trying to lift a series of points is very large.

Can anyone help?

You have an issue with not enough graphics power.  The larger your base boards, and the higher the grid, the more graphics power is needed.

 

Would it be better to use several  small boards joined together?

Small boards joined together would decrease the graphics load on the computer, but it would be necessary to make some invisible when landscaping.

Thanks for the advice. I am now using boards 200 x 200 and it works