Using the LoadPicture function its a one liner! So there is no loop to be able to have a progress bar increase. The only problem is with this one liner the larger the graphic the longer it takes so it looks like your program freezes for a moment but hey thats VB.
The only other way to get around this is to create a loading function yourself. Then you can place code in the loop that reads the bytes to increment the progressbar, but any thing that you come up with will take at least twice as long as the loadpicture function.
BTW, have you read FAQ222-2244 yet?
Good Luck