How to draw arcs of arbitrary angle, or defined by tangents in Visio?

I am using MS Visio 2013, trying to draw a circular arc which spans between two 45 degrees lines. Think about an isosceles right triangle, where the head (90 deg) vertex is trimmed to a circular shape of a given radius.

The ultimate goal is to create a pincushion shape made of 4 such arcs. Here's my current shot (resized for showing details). It was made by drawing a 90 deg arc using the arc tool (from 0 deg to 90 deg), then rotating the shape, using the 3-D Z Rotation in 45 deg.

As you can see, the connection of the arcs with the diagonal sections is not smooth and overlapping.

Questions:

1. 
   

   Can I draw an arc defined by its start and end angles?

   
   


2. 
   

   Can I draw an arc defined by its start and end tangent lines?

   
   


3. 
   

   Is there a pincushion shape hiding in one of the sets (it has the advantage of being opaque, and you can set the internal color)?

   
   

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