This is a big need of mine, too. Similar use as @Raul_San_N.H you are describing - I have a lot of need for Coda that your excellent templates in the gallery are more or less designed to fill - bug tracking, lining up user feedback and cataloging to certain missing features, and a few others.
I think a good analogy here is when you fill in webforms in your everyday use of the internet, in particular shopping carts or sign ups on apps, you will frequently not be able to complete the process if certain fields are not filled out. They turn “red” at times when you hit “submit” so the user can go back and complete them.
And one particular way to use this that would be very helpful is to force a comment to be added to a row when an action is taken. Ideally the row would be set up for the comments window to “pop up” and require a comment before completing the action. This is very useful in the case of processes being run in Coda: You might require a comment when the status is moved to “done” or “complete.” If you have a column for “status,” and you could with automation require a comment before the final status was accepted, you’d have a very powerful feature for end users to easily remember to notate what they actually did to close out a process.
I wrote about this in another thread here, too:
Really eager to see this feature, thanks guys!