The prize has gotten a bit better now. A striped lolly has been added. Now 5 levels. Edit it's 4 levels. Just passed the very difficult 4th jam level by setting up a colourball/colourbomb combo with a lolly. But at least I gained a striped lolly.
I had the dimmed screen sometimes, I either logged out and logged back in, or I had to reboot/switch off my device. Most of the time I works, and I got the goldbar back too.
Didn't have BGH for ages - now after 1 week back, I have 144 gold barrels - I am using all may old Phones with bad akku, so I can play BGH on 5 devices a day - and I love it.