Since there is discussion happening elsewhere about this, and this forum is mostly about add-on development, I'll stick to the technical side of this argument.
Add-ons that change Firefox settings need to revert those settings to their previous state when the add-on is uninstalled. As I understand it, your add-on changes settings, and the latest versions you have submitted revert these settings to their default value which is different to what we're asking.
So, just as an example let's say the preference has a default value of 0, your add-on sets it to 1, and before the add-on was installed the user set it to 2. When the add-on is uninstalled, the value should be set back to 2, not 0.
If this isn't clear somehow, please let me know. You can try posting your question in your native language and maybe someone else can help with the translation.