The difficulty will depend, I'm sure, on the coder's ability to analyze the processes in this small mod (mostly gives extra function to a specific type of attachment in the post/thread structure, and interfaces with external software). Not being a coder, I'm sure there's a simpler way to describe that, but I would prefer to leave specifics to a direct conversation. Truly, I don't expect it to be a major undertaking, even if there may be ways to improve upon it (maybe tying it into RM, for example). Adapting some of the output to responsive will be important.
Shoot me a conversation if you're interested, and would like further detail.