Where is CadPHP document root path

Anybody managed to use cadphp successfully and clarify what is meant by document root in the instructions.

The test example works “cadphp:p1:test”
but after copying test.php to my document root i.e location of .md file,
Setting Path P2 to \ in plugin config
Calling “cadphp:p2:test”
it does not load the file.
Looking at the HTML result file , it is totally ignored which suggests the path is incorrect.