Described behavior can be caused by incorrect font specification. Please check that your script options and fgl_setproperty("gui",...) calls that you use in your 4GL application to define font style correspond to the following rule:

<font name>-<font weight>-<italic>-<other attributes>-<size>-<character set>

(refer to Hydra4GL Graphical Client ref. guide.pdf, page 39 for more details)

Here are some examples of correct font specifications (draw your attention on the all five "-"-signs that have to be mandatory defined):

Arial-bold---10-

(Font Arial, bold, size=10)

SansSerif-bold-i-us-9-

(Font SansSerif, bold, italic, underline, strikeout, size=9)