A user reported via a forum that he has some issues with the built in SQL editor of the TAdsQuery component. In most cases the complete IDE just freezes. The easiest solution is to get rid of that editor.
Launch Delphi as Administrator
Open the design time package \program files(x86)\Advantage XX\TDataset\Delphi XX\Win32\Source\adsXXdstudio.dproj
Then search for the RegisterPropertyEditor function calls in adsdesign.pas. You’ll find something like
RegisterPropertyEditor(TypeInfo(TStrings), TAdsQuery, 'Sql', TIDEQueryUtility);
Put this function call into a comment or remove it. Then compile the package and install it.
Now editing the SQL property of TAdsQuery will open a simple text input window.