What Wink said, but you also need to consider the actual player sprite object and how it gets to the new layer.
Select the player sprite and look at the properties panel. In the first group you'll see a "Global" parameter. If this is "No", which is the default, then 2 things happen:
a) The player object won't appear on the new layout unless you place it there, either at design time or by creating or spawning it.
b) The instance variables for that player object are reset to the defaults in the new layout.
However, if you have global set to Yes, then:
a) The player object automatically appears on the new layout in the same position it was in in the old layout (but you can reposition it, of course.)
b) The instance variables that changed in the previous layer retain their values in the new layout.