Help needed on UML Shape change (state.c)

[myken <myken iae nl>]

Hello all,

I'm trying to make a new copy of the state shape from the UML sheet.
I have managed to create my own sheet and my own shapes using some
copy-past techniques and the draft tutorial from Thimo Langbehn. So far
so good. I managed to change the line colour of the "state.c" shape (now
called mystate.c). 
Now I would like to change to position of the connection points in my
copied shape (mystate.c) but I don't get it to work.
Simply replacing the function call in line 393:
392:  /* Update connections: */
393:  element_update_connections_rectangle(elem, state->connections);
with my own function doesn't do the trick. I have no clue where to start
looking. If I look at other shapes e.g. "box.c" they are implemented
differently so I kinda got lost.

My aim is to move the connection points at the corners more closer to
the center points.

Does anyone have an idea where I should look/start?

Thanks,
Robert.