Trying to get a multimodel routes

We are trying to get a multimodal route between two routes with the help of transfer file ,
but its not working .
It will be helpful if we get a proper doc or steps for the requirement of GTFS what Graphhopper needed to give result.

The setup is described here https://github.com/graphhopper/graphhopper/tree/master/reader-gtfs

Please keep in mind there is still this issue: https://github.com/graphhopper/graphhopper/issues/1023 still if you just use pt the foot network will be used for start and destination.

okay… let me clear my question more.
i have two routes and two trips in my gtfs which have a comman point of stop.
i created a transfer file and added a row

'“from_stop_id”,“to_stop_id”,“transfer_type”,"min_transfer_time"
stop_tr_307,stop_tr_307,0,
stop_tr_307,stop_tr_502,0,
stop_tr_502,stop_tr_307,0,

i inseted
source is from route 1 (start of route 1)
destination is from route 2 ( any stop after common stop)

i was expecting a result like .
it should take
source( part of route 1) to common point and common point to destination( part of route 2).

but its not working like that.
m i doing something wrong ?

or how transfer work for multimodal public transport ?