I've noticed an issue several times where the Powerpoint slide thumbnails don't appear when I load a service that had a Powerpoint added to it on a different computer. All I get are blank buttons that I can click in the controllers. The powerpoint runs fine and displays correctly on the projector, just not in the main OpenLP window. When I add the Powerpoint to the service I get the thumbnails, and if I close OpenLP and then re-open that service on the same computer I get the thumbnails, but if I then transfer that service to another computer and open it, the thumbnails are missing. This is happening in OpenLP 1.9.8 using both Powerpoint 2007 and 2010 on Windows 7 64bit.
Normally I end up getting the Powerpoint last minute right before the service so it hasn't been an issue, but I've had one instance where I put the entire service together on my computer at home and then opened it up on the computer at church to discover the missing thumbnails which was very disconcerting, and when I open the services later on my computer at home I notice the thumbnails are missing. I didn't see this mentioned in the forum so I wanted to bring it to your attention.