Subscription within a process

Hi all,

in one of my process I’ve got two steps : let’s say stepA and stepB ; I’m trying to make stepB wait for a document coming from another treatment

step A is building a request in a form of a document called ‘docRequest’ ; i set the docRequest as Publication of step A.
docRequest is triggering another process, which ends up publishing docAnswer
and stepB of my first process is subscribing to docAnswer

and what happens is : when docAnswer is published i get the messages

(T61) *** NON-START STEP ***
(T61) step N9 of model P-17974771185213 is a non-start step

and the step keeps on waiting

i thought it would work cause i saw this in the Modeler Guide :

(page 92)
and the explanation going with the model confirms it should work

has any of you sorted out a similar situation ?