KFF Custom Form Window doesnot Pop Up

KFF does not pop up in the custom form - Form Triggers:

Solution:
Triggers in the KFF item should be modified as below:
WHEN-VALIDATE-ITEM
if ( :system.mode = 'NORMAL' ) then
fnd_flex.event( 'WHEN-VALIDATE-ITEM' );
end if;
WHEN-NEW-ITEM-INSTANCE
app_standard.event('WHEN-NEW-ITEM-INSTANCE');
fnd_flex.event('WHEN-NEW-ITEM-INSTANCE' );
POST-QUERY
--Loads the flexfields (in our case, it populates --the concatenated field on execute query).
FND_FLEX.EVENT('POST-QUERY');
PRE-QUERY
--If you don't do this, whatever query criteria you may enter in
-- the concatenated flex field, it is not taken into account.
FND_FLEX.EVENT('PRE-QUERY' );
KEY-LISTVAL
APP_STANDARD.EVENT('KEY-LISTVAL');
FND_FLEX.EVENT('KEY-LISTVAL' );