Vishnu,
I was actually figuring you'd come back and suggest the Event Type adding of the parameter. 
We implemented the "select" logic and confirmed that the control parameters and expected events table are not committed for the ZCREATE event so we implemented the TOR_TYPE back into the Event Type.
The issue is we are getting a dump though when we unassign the FO and then replan it. We get a duplicate key dump on table '/saptrx/eh_evmsg'.
If I have the following code commented out everything works; is anything you notice in this code that could be wrong or causing the issue?
lwa_trackparameters-partyp = 'C'.
lwa_trackparameters-param_name = 'Z_TOR_TYPE'.
lwa_trackparameters-param_index = '0000000001'.
lwa_trackparameters-param_value = <fs_tor_root>-tor_type.
lwa_trackparameters-action = 'C'.
APPEND lwa_trackparameters TO ct_trackparameters.