My pleasure - only hope I can be of some help.
OK - so you have your tour and, lets say, the final scene is the one which has both day and night shots.
Set your day scene up this way...
add your scene
double click on it to change the main window so that all you see is your -ano scene.
then look at the top of this image and click on the 'immersive' setting. This will let you see your rotatable panorama inside the skin you have chosen/made.
then look at the 'properties and actions' panel (which is usually below your working window).
Look at the 'pan initial' number. Either type a number in or click on the arrow to the right of the number entry box. Moving this by either method should see your pano scene rotate. Leave it facing the direction you want your users to 'look in' first.
Next, I'd recommend changing the 'speed' setting to 0 - then it users will not have the scene rotating automatically.
Then add in your night shot to your 360 panorama list.
Double click on the image so that your window now shows your night pano. DONT change to 'immersive' here.
You could make a button which you use with your 'day scene'. This button will need to have the following - add the button, then click on 'actions' in the 'properties and actions' panel.
click on 'scene and movie' (in the list to the left of the 'properties and actions' panel).
Choose the 'link to scene' and then use the 'plus' button to add this action.
a little window will now appear. Select your night pano and use the 'pan' setting so that your users will now be 'looking' in exaclty the same direction as in the day scene.
This should work. As I said, if they move around in the scene the replacement 'night' shot won't start facing in the direction they left the day scene in. BUT - if the users have to rotate round to see the 'click here for night view' button (or whatever you wish to call it) then they will be facing more or less in the direction you want.
Hope this is clear!