Tasks without Iterations in Agilefant 1.6.2

There is some confusion in Stories in Agilefant.
When Story is inside the Project, I can assign it only TODOs, but no Tasks.
When Story is inside the Iteration, I can assign it a Task and inside the Task there will be TODOs.

The question is: why I cannot assign a Task to Story inside the Project?
And why TODOs have no Estimation time?

Questions are connected: if I divide my Story to some parts, I wish to assign them an Estimate.
So either Estimation to TODOs, or Tasks in the Project Story or both