I've been doing quite a bit of the work with the form builder. There are a few big improvements to it coming with the next release of concrete5 (file upload field types, required fields, question versioning, etc). The form block has been making a lot of progress lately, but it probably could be refined somed. thanks for the link. In your demo, I like that it is a little more edit-in-place style, but it could be more so. I don't like the needing to right click to see the possible fields. Most people don't think to right click, and having to "teach" them with a set of instructions doesn't seem like a good approach. I like the option there of being able to set the initial value of a field and the error message (although the error message field should probably disappear when the required checkbox isn't checked). Maybe you could just type in the fields in our preview screen to set the initial values? something to brainstorm on I guess...
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