"Limit listing of subscriptions" exposes hidden groups and does not work properly

We have a problem with how the settings of the OG email notifications are translated into the OG Sububscriptions module. It works perfect for the users with the options "Never send email notifications" and "Selectively send email notification" checked (no OG subscriptions/only as set up by the user). However, it is not really working for those with "Always send email notifications" checked - they are subscribed to all groups, even those that they are not member of. Even worse, with the setting "Limit listing of subscriptions in account(user/#uid/subscriptions/group) to those where user is member." enabled, they have no chance of changing that: we have 17 user groups and users who are a member of just one will now see that they are subscribed to 17 groups but can only change the settings for the one group they are a member of. I can of course uncheck the "Limit listing" setting, but it still means that we now have hundreds of users that are suddenly members of all groups on the system.

I think I do understand why the three OG notification settings were translated into OG Subscriptions that way, after all "Always send email notifications" seems pretty global. However, with OG Notification this meant that you would always receive emails but only for the groups you are a member of - now you get them for all groups! I think what the "Limit listing of subscriptions..." setting should do is not simply to limit the display of subscriptions but to actually ensure that you are only receive email from the groups you are a member of.

I would love to use this module but it does not seem right to go to hundreds of users for whom the settings worked fine and to ask them to change everything manually. Also, the way it is set up currently really all groups are shown to the users, including those that are not even listed in the groups directory. This is problematic as it means that a) users do now know that these groups exits; b) users will either receive notifications from groups that they are not a member of (bad, especially for private content in these groups) or the system makes them believe that they do receive such notifications even though they will not get them.