hello!!
well the tpf_NextPos is not the native function in my plugin but a optinal function . it's defined in "tpf_extra.c".

if you look into the function you will see this function shall combine a ENTITY pf_obj->ent.

the tpf_NextPos's Algorithm is that this function use thepf_obj->ent' postion to check if the entity is enough closed to the first node in the path ,if yes then remove the first node. then check if the entity is enough closed the new first node ( the post second node) and so on............

so obviously for use this optional function , you should bind a entiy to the pathfinder first.
for example:
enemy_finder.ent =me;

hope you think my plugin is a bit useful....

best regards tang ziwen