Somewhere between RC4 and RC8, something has changed in the way that a refresh is handled, which causes a filled in (grey? white?) bounding box to flash momentarily on the screen when DeskTask does an update. I thought this was a graphics card issue, but it's not: it happens on three separate machines, all with different graphics cards.
I suspect it started in RC7 when transparency was added, but I can't be sure because I don't have RC7 or RC6 to test it with. I'm not familiar with the API for transparency but I suspect there's a difference between displaying with no transparency set, and displaying with 0% transparency.
The transparency of the flickering box is affected by the transparency setting in DeskTask: set to 95% transparent and the box does appear but only very faintly.
I used to have DeskTask set to refresh every five minutes, but it's now set to once an hour because it was getting too irritating.
If you want to test whether it happens for you, do a manual refresh (RMB on tray icon and choose 'Refresh') and watch to see if the DeskTask area flickers.
James | 
