Maurilio,
>The intention is paint the border with a different color to mandatory fields (for example) to let the user have a visual reference.
That is what the pink field is in the example screenshot in my previous message. I have no mandatory fields as explained in my previous message, I call them critical data, but these are what you would call mandatory. They are pink until filled out, then they become white. Or, they could become yellow if the data is suspect.
As I said, if you make fields mandatory and the user doesn't have the needed data, then they will make something up. (I assume by "mandatory" you mean that they must be filled out before the dialog can be saved.)
>Using themes under XP we have controls with line border or "flat style" but who don't use themes or Win98 don't have it. The only way I found to use this flat borders and colored references is changing controls for myself.
You can use field colors in all versions of Windows, and you don't need to modify the FW source. Also, it works with or without themes.
Regards,
James