Lookup Form Closes after Click to StringEdit Control Ax 2009

Hello,

I have Ax 2009 Lookup forum and i am calling this Form, from a StringEdit Control of another forum. Everything goes ok, the form opens and gets the chosen value and sets it back to StringEdit control when i click on any chosen Gridview Row, but when i click any of the controls on the lookup Form, it automatically closes. I have 3 filter controls on that form which i use to filter Data source. I want to be able to click on these controls and use them to filter the DataSource. Then, click the chosen Grid Row and return it back to Calling Control. I did all the necessary thing but i am still having this trouble.

Options Set on the lookup form are as follows:

AllowCheck:    No
AllowCreate:   No
AllowDelete:   No
AllowEdit:     No
AutoNotify:    No
InsertAtEnd:   No
InsertIfEmpty: No

      AlwaysOnTop:   Yes
      Frame:         Border
      HideToolbar:   Yes
      WindowType:    Popup



Please, can anyone of you help me with this problem?

Thanks a lot if you red this.