@artpen I see a few questions in your attached image:
re: Is there a way to control the number of floors
Sure, you could create an Assembly with a single floor as a component:
Once you’ve got the right amount of floors, you would make that end product into a component and then use that component for your horizontal assembly.
re: How to adjust the ends so they join correctly
In the Assembly dialog, you’ll see the Left/Right Offset. You can adjust that number for each part of your assembly to adjust how they meet up. (I downloaded your file and couldn’t see where the fix would specifically be for you - I’d need your Assembly file. But you could fix pretty easily using the offset.
re: Overlapping problem
In your file, you don’t have the overlap issue except in one case on one side, and a second case on the other side. It seems like you may have just left the original components (that you turned into Assemblies) and your Assemblies are overlapping them (in which case, you can just remove them). If the issue is indeed within the Assembly, you fix it by adjusting the Spacing value.
re: Random balconies with Span
You can’t get a random distribution using Span. Your best bet would be to have some regular pattern, and then come through and delete some here and there to come up with something more random.