First of all, none of the similar topics helped me.
I've exported a form and imported in another (local) site.
I can edit the form, but I can't preview it or view it in a post.
I've tried the meta recover tool, but it didn't help (no error messages).
This is happening also with new created forms by the way.
I believe this is also related to a customization I've made to GF that adds a new form setting (see here).
I suppose that this new setting, even though it works on the form editor side, is messing up the meta data, but as there is almost no documentation about how to do this, I'm unable to understad if this is the actual issue or if something else is messing up my forms.