Andy.
you wrote the following reply.
Thanks, Alan.  You're right.  I can open it now via the VC.  But how do I close it again (some people are never satisfied, eh?)?    It's just that I don't have that roving camera software - yet - and my fixed view of the VC doesn't include the floor hatch you mentioned.

i dont have active camera either,i just use the basic ms eyepoint controls to move about the flight deck.if you use the hat sw to look aft,then down onto the p1 seat,then use eyepoint back control until you can see the steps of the entry door,on your right,the hatch is then at the 10 oclock pos,click on it to close the emg hatch,then use spacebar to reset the eyepoint,the keys i have asigned to the eyepoint movement are as follows,A=BACK/B=FWD/Z=LEFT/H=RIGHT.
hope this helps you.
regards alan. 8-) :)