There is a guide to developing addons here:
https://docs.phpvms.net/developers/addons
With a sample plugin created here:
https://github.com/nabeelio/phpvms-module
If there are issues, something is missing, or you just have questions about best-practices, let me know. Any addons that aren't created in this way will a) have a good chance of messing up someone's install b) get wiped out in an auto-update, and therefore, will be locked and removed until they're compliant. I know modification and addons are a huge draw, so I'm not trying to restrict that, and yes, the process is a little more complicated and there is a learning curve, but it's for long-term viability and the good of the ecosystem that these rules are going to be enforced.
Your addon should also be submitted here:
https://forum.phpvms.net/files/category/8-add-ons/
Thanks!