16 months and nothing was done!
Not an easy task but it could have been resolved in stages - TRT did allow for that.

So now Zerif Lite has been suspended and instead of working on a resolution all thats happening is arguments going back and forth - all the while throwing in the end user whom non of this actually helps!

Develop and release Zerif Lite 2.0 with a companion plugin as suggested.

The companion plugin should be designed is such away that it checks as which version of Zerif is active - so if its the old version then the old data is retrieved and if its the new version then the newly introduced CPT are retrieved.

At the moment for the Zerif team the sticking point seems to be the question of data portability. This will only remain an issue if the companion plugin is designed to function in the same manner as the current theme does.

Solution is, old theme active use old data - new theme active use new CPT data.

Within the old version of the theme on a theme specific info page inform users that with the current theme the data in xyz sections are not portable while they would be in the new version.

The question of data not being displayed on another developer's theme is irrelevant as that is a choice the use makes when they change themes. However the data is still there, safe! (its like having a car with a tow bar and a caravan - you switch to a new car with no tow bar but you still have the caravan :) )

Make the new version as awesome as the first and soon or later most of the 300K will transition over - those who choose to remain on the old version will still have a perfectly functional theme and continue to receive updates addressing any security issues.

Some may argue its not the best solution and I would argue that its a step in the right direction for the end users!