This is a very nice project indeed
Thanks for taking up this challenge.
I have a question tho: have you thought about the license of this module/script? As you can read
in this forum thread and
this FAQ entry, the XOOPS project's interpretation of the use of the GPL license is that when a script depends on XOOPS code that is released under the GNU GPL 2.0 license to function (read: can't function without it), it is considered to be a 'derived work' of the XOOPS system, and therefore should be licensed under the GNU GPL 2.0.
I am not sure, but it seems like what you're describing needs the XOOPS codes to function properly. There is nothing wrong with that of course, but I am guessing that you want to restrict the people that buy your subscription script for $10 from distributing it for free to the rest of the world. And the GNU GPL does not allow you to put any restrictions on the use of the code.
This post is not meant to stop you from doing what you're trying to do, but to introduce another way to get something back from the investment you have made, or are making.
What about requesting for investors: people who donate funds for you to have the module developed. And when you have enough, you release the module for everyone to use. That way you'd be within the limits of the GNU GPL, contributing to the community, AND we introduce a new way of getting modules developed, commercially. The main point here is that selling the code is not the way to go in an open source community, but selling services (like development, but also design, implemntation, hosting, customisation, training, support) is the future.
So, to summarize: ask for investors, give them some room to add features for their money, and when you have enough, you release the module. You can always ask for donations with the released module, but do not restict how people can use and distribute the code.
Herko