One reason we distribute both PNGs and RSRs for the thumbnails is that sometimes Pro Pack screws up when it is trying to convert the RSR to a PNG. This seems to happen in thumbnails where most of the middle of the image is empty. (Imagine, for example, a close-up of a door frame, where you have something like an upside-down, squared-off letter U, with the middle part empty.) By creating an RSR, then letting Pro Pack convert it to a PNG, we know that we have a good PNG. (I suppose we could let Pro Pack convert it to a PNG, then throw the PNG away and just ship the RSR, confident that it is convertable, but I am a little more comfortable shipping my own PNG, and not depending on the user's copy of Pro Pack, at an unknown [to me] service level, converting it properly.) Lynn Grant Castle Development Group