I just wanted to tell you something, don't know why it is that way:
I am using two PC's - 1) ASUS eeePC running on Linux Ubuntu, as it is a small 'netbook' it has very weak CPU/RAM/graphics - on this pc this shops-problem happens to me, too - every time!
2) a common desktop PC, with way better 4GB RAM, NVIDIA (8400GS) graphics card, and also a better CPU - all in all a faster, average gaming PC - on this pc I can claim my daily chance on shops without any problems...(it happened once or twice, but when I tried again the grant worked)
- so, this may be connected to the problem? Because if you leave the page open for a while it works (like BackWardForWard said)...maybe it's a speed problem, depending on how fast your computer processes the page?
another difference between those two pc's is: the eeePC opens the non-animated, nearly blank page to click "claim your reward" when I want my daily chance.
the desktop pc opens the small window on-page which is animated (you know, the one with the stars flying around xD)
This, too, seems to be depending on what pc you are using (slow pc - not animated, faster pc - animated)~
....now I've talked that much, maybe for nothing, but I just wanted to share what I experience every time xD