Hi,
I hesitated to answer yesterday, because I can't really give any useful info on your specific requirement... but, even if the form is a relatively simple one, I'd put the technical challenge in the same category as printing a smartform to, say, an mpeg video 
What business need/requirement would this OTF->Excel converter actually cater to..? It should IMO be something really critical and central to the business to justify investing in developing (and maintaining!) something like than inhouse.
Have you already considered outputting Smartform as XSF, HTML or XDF (out of the three only HTML will attempt to preserve layout).
cheers
Janis