I have a similar issue. I add a new column to content type list in SharePoint UI & reorder the content type the way that I want. I mark the checkbox to update content type list. Ideally, I should be able to add a column in SPD & reorder them. Unfortunately, SPD doesn't have an option for me to reorder column & add a column. So I had to do it in SharePoint UI. But after adding the new column & reorder columns in SP UI, in SPD, I look at the content type order, it's not in order that I'd seen in UI. Therefore, my custom form didn't reflect the order of the fields displayed on the form. If I know how to make the order of content types cascade to SPD, then the form should reordered, right? or Do I have to recreate for form?