Firstly, regarding the callout issue, theoretically the callout is just another view. So it behaves like any other view - anything you model inside the callout will exist in the whole project.
I tested placing rebar in Revit Structure 2013 in a callout (Detail callout for both sections and plans) and it worked just as in the main views.
Could you give some details about what error messages you received when trying to place rebar in a callout?
Secondly, another issue I understand you are experiencing is placing rebar in columns in a Plan Views, which is indeed a bit tricky.
When trying to place rebar in a Plan View, Revit recognizes the current work plane as being the current level.
Since the column probably starts on that exact level, the current workplane is not viewed by Revit as intersecting/being inside the column.
My suggestion is to follow these steps:
- Create a Reference plane in an Elevation/Section View that is above the current level, and so intersects the column.
- Name the plane as you wish, so it will be easier to find afterwards
- On the floor plan, before placing the rebar, set the current workplane to the plane you just created.
- On the Ribbon -> Structure -> Work Plane -> Set -> Name
I also recommend this video explaining the placement of rebar (longitudinal and stirrups) in a column.
https://www.youtube.com/watch?v=L_wmxJRy_EQ
The same tips should work on a rounded column as well.
I hope this helps.

Alida Popescu