How can we expand cells in grid by horizontal position? It will be nice to expand two Output Text cells in one.
Right now, expanding cell horizontally (colspan) isn't supported in Form Builder. Only expanding cell vertically (rowspan) is supported.
You could update the source of the form to add a colspan where necessary, and remove unnecessary xh:td, but I wouldn't recommend doing it: since Form Builder doesn't take those colspan in account, it is likely to break the structure of your table when you later add/remove columns or extend cells vertically.