Custom validation with related object

I have added a custom validation. The validation I’ve added is to prevent ‘localhost’ as part of an url in a http connector in a process flow. This works, however, the columns pk_col_1 - pk_col_7 are a bit of magic. As far I can see they are used to calculate what to show behind the tab ‘Related Object’ in the validation screen.

In this case i want the related object is reflecting the following address:

I notice there is a column “Object type” which is not documented, but I think does affect what the values of pk_col_1 - 5 needs to be:

But what Object type should I choose in this particular situation?

And with what values the pk_col_ columns should be filled?

I currently use this query:

insert into validation_msg (project_id 
 , project_vrs_id 
 , validation_id 
 , pk_col_1
 , pk_col_2
 , pk_col_3
 , pk_col_4
 , pk_col_5
 , generated 
 , insert_user 
 , insert_date_time
 , update_user 
 , update_date_time)
select
 @project_id,
 @project_vrs_id,
 @validation_id,
 @project_id as pk_col_1,
 @project_vrs_id as pk_col_2,
 pafip.process_flow_id as pk_col_3,
 pafip.process_action_id as pk_col_4,
 pafip.input_parmtr_id as pk_col_5,
 0,
 dbo.tsf_user(),
 getdate(),
 dbo.tsf_user(),
 getdate()
from process_action_fixed_input_parmtr pafip
where pafip.project_id = @project_id 
 and pafip.project_vrs_id = @project_vrs_id
 and pafip.input_parmtr_id = 'http_con_url' 
 and pafip.assignment_method = 'literal_constant'
 and pafip.constant_value like '%localhost%'

With the query and settings as above I get an error message in when opening the tab page ‘related objects’.

I know this is a bit of an advanced feature (it's quite hidden in ‘full model’, and you do need know how the SF-database works a bit), but could be very usefull (when properly documented).