I've created a plug-in activated using a Plug-in Extras menu which does an export by setting up the export session in an asynchronous task and calling doExportOnCurrentTask()
This plugin works fine on a selection of about 90 or fewer images.
If I try to run it on more images, a "Preparing to export…" progress dialog appears and starts to make some progress. Then an error dialog appears:
An internal error has occurred.
?:0: attempt to index a nil value
An export from the Export menu with similar settings works fine on the same selection of images.
Has anyone had a similar error when doing an export from a plug-in?
This problem seems to be with the catalog, not with the plug-in code.
The catalog is large and was created with an early version of Lightroom. Some of the records seem to be corrupted.
The keyword field cannot be edited on these problem records, and they won't export.