One odd behavior we have noticed in Forms is that, when the Form loads and a field gets populated via a lookup, all other required fields get highlighted in red and display the "Please fill out this field" message under them. This leads to an awkward user experience and is confusing for some less tech-savvy users.
It is especially jarring if the user is adding table rows where drop-down field options come from a lookup table. Each and every single field prematurely goes through validation.
It's pretty obvious behavior so I assume development is aware. Is a fix for this coming in version 10?