Problem to Convert Solid Bodies into Sheet Metal

I am trying to convert a import bodie into sheet metal.

Some parts is converted, but i have problem into convert some bodies.

After to open the imported part, the FeatureWorks is starded and i select the Yes.

The FeatureWorks can't indentify the Extrusion (Corpo não reconhecido):

The final results is:

When i am try to convert into sheet metal, is not possible to select the Flat Face:

Some parts is possible to convert into sheet metal and other is not possible.

The part is attached in the first comment.