Control over Data graphics callouts in org chart

[Gemma]

Hi, I'm really praying someone can help me, cause I've been on this for quite a while now and unfortunately not succeeding 
I built the org chart for the place I work in, in view of an acquisition.
Took me long enough already to build a proper database I could use with a unique ID.
Now, I have a list of the graphic data I need to display:
- AnnexNr (text)
- ReqNr (text)
- WorkerType (icon)
- EndDate (date)
- PositionNr (text)

Given how the page is fully packed as is with the shapes alone, I cannot afford Visio placing huge callouts all around each shape, so I have a defined placement for each of the fields.
Here's where it gets tricky:
1) Not everyone has an end date, so I need the callout to only appear if there is a value in the field (currently displays a zero if empty)
2) They need to show only some of the values for different audiences, but if I uncheck and then re-check the field in the Data Graphic Fields pane, Visio creates a new set and the value displays the way Visio wants and not how I set it up initially.
(see attached example)

Is there a way I can have the value go back in its defined place?

Forever grateful for any help