hello ivan, look the metadata.json file should only refer to the manifest.webapp, no science there, i have sent you an email including the files of an app, a custom app and textr, you should try it out
i got a successful installation of many apps, however, these apps are for touch phones not a keypad one, if only i can extract apps form this phone and them modify them
here's an example of metadata.json
this file should be present with another file named manifest.webapp
to be able to install an app you have to
and include the modified metadata.json with the app files
change it to
and rename the update.webapp to manifest.webapp