What is the general goal of the feature?
Uploading a new version of an already submitted response.
What are the most likely user stories for how and when this would be used by someone on your team?
A volunteer goes through a slums making surveys and realizes that he or she needs to access an existing case (not uploaded by her) and generate a new updated version of it.
Can you sketch out graphically how you think this should look/work in practice?
How useful would this feature be to other users or organizations?
I think it would have great value for organizations do recurring survey work. Many organizations want to know how cases evolved through time for research or operative reasons.
This feature helps to extend kobo in that direction, supporting teams that make follow up work.
What can you contribute to making this feature a reality?
TECHO could help with funding, we could consider fund it by ourselves -to cover developers and related expenses depending on the whole cost- or by applying together to international funding (like this for instance)
A complete user story with a user case can be found here