Using the example for BMI Calculator by Gizmo, I was able to replicate the experience.
However, there is one problem with the calculation button that appears only in Build page, and not in Preview page.
Would you please help to answer?
I really need it. I tried to incheck “Automatically verify and fix this question’s HTML” in the Custom group and every sub-question but to no avail.
Thank you very much for all your help in advance.
If I understand you correctly, it may be that when viewing the preview, you have not set the “Fire Actions” toggle at the top of the preview page to on.
If you try the share link, you may see that the button works properly.