There aren't many alternatives to Templot for designing handbuilt track, but there is a new kid on the block from Andy Reichert & David Honner. There is a free trial version available:
CTnCT Designer: http://www.proto87.c...T_designer.html
Other alternatives to Templot are:
TRAX3 from Jeff Geary: https://www.amazon.c.../dp/1906419612/
Just to add that Templot is free to use, the others above are paid-for software.
(There are lots of other track planning programs of course, but none of them are much use for designing handbuilt track templates.)