Ashley > This is actually worse for memory management. Construct can only load or unload entire objects in to memory. If lots of objects are combined in to one it forces Construct to load everything, making it likely memory is wasted. If they are kept as separate objects there is better granularity to load some but not others, saving memory.
Group all the sprites that always appear together and only with the platforms the game needs 300 megabytes less.
This is the sprite sheet.
It is much more effective than this, which is what generates C3 by default.