gluing text boxes to connector stencils?

[johnnygeo]

I am making a flow diagram that needs to show volumes moving into and out of a series of nodes. I would like to connect the node shapes to each other using line-curve connectors. Each connector should have a text box near each end. I tried editing the line-curve connector master but I can't get the text boxes to stick to the curve itself - as the curve shape changes, the text boxes stay in the same location. Any help greatly appreciated, thanks.

rgds,
JohnnyGeo

 

[johnnygeo]

I'd settle for a mathematical expression to use in the shapesheet to position a connection point exactly on the curve.