A320 Missed Approach without sequenced waypoints
 

According to the FCOM NAV mode is not available if initiating missed approach without sequenced waypoints.

For anyone who has seen this situation in the simulator ( or in the aircraft ), what is displayed on the ND ?

The BLUE missed approach course is displayed if at least one Missed Approach waypoint is on the PF MCDU. So after the FMGC enters the missed approach phase ( assuming no Blue line is available before ) does the ND continue to not display any course indication or something else such as a dashed blue line indicating the course to follow in a selected mode?

MANTOGA/SRS/GATRK this is what you get. It will not change to NAV. So pull HDG and fly the procedure manually.ND will show the procedure keep rhe aircraft on it.

Be careful if you are given radar vectors on approach which take you through the missed approach course as you will lose the flight plan. Sorted by inserting the airport as a new destination and adding the approach or activating secondary flight plan.