This is more of a feature enhancement/product improvement suggestion than a bug.
I was making a simple temperature and humidity sensor and while there is a special type for CloudTemperature humidity is just a float value.
It took me a bit of digging to find this out as I tried to define the humidity as CloudHumidity and verification failed. By happenchance, I hit the edit sketch button in IoTCloud and hoped it wouldn't wipe out my changes. That's when I found out it was just expecting a Float.
I'd expect either the type to be marked in IoTCloud when I make a new variable (Since I'm picking the type) or to have some documentation (other than source code) on the types available and how they map.