(Windows Vista). The indexer seems to crash periodically while it is doing (another) first time indexing.
The cause of the indexer crash seems to be that new resources are available for download.
As soon as windows reports that the indexer has stopped and the crash window is closed, then Logos 5 imediately starts to download the new resources / updates and then wants to be restarted. Indexing then resumes until additional resource updates are available for download.