If you use:
application.showFormInDialog(forms.relaties_zoeken,-1,-1,200,500,‘Zoek Relatie’);
and you use -1(center) for the x and y , than the widht and height values are not working anymore!
bug confirmed. You explicitely have to enter xy position in order to make xy size work. Will pass to dev team.
Thanks.
fixed in 1.2 rc5