I like the XLC functions and toolbar. Very nice.

However, I have a problem with the expiration policy. This policy seems like a big disadvantage. The thought of writing a spreadsheet which will expire in the near future is enough to keep me from using these functions in some cases. A thought that will occur to many users is that you will stop issuing updates and renewals because you decide it is not profitable or some other reason, and so our spreadsheets will all expire with no hope of making them work again.

A suggestion:
Since you are offering it free, why not offer updates to subscribers but not use an expiration date. It seems like piracy wouldn't be much of a problem since registration is free. If monetary compensation is a concern, you could offer updates or a more advanced version for a small fee. This is what many software writers do. Please do away with the expiration.

Thanks,
MAJ