I just happened to have my playfield out and heres a couple of pics of flipper coils. let me know if you need more or a different angle20140722_192401.jpg20140722_192438.jpg20140722_192558.jpg

I don't know about the locked ball thing . mine hasn't been working long enough to get into that lol. I should have it back together tonight after touch up and clearcoating the playfield. I just got my rottendog mpu board back from jim, so hopefully everything goes well. I do know that at end of the game any locked balls remain locked, unlike my xenon at end of the game the are ejected. you might try a switch test in the diagnostics to test your leaf switches and such. but make sure you do it with a pinball in the ball troughs and not your finger. sometimes the ball will rest differently than if you push the switch by hand ive noticed. if you recap the power supply board you should follow vids guide its very good and he knows his stuff. I did everything in the guide except the 5volt regulator which I understand rarely goes bad, but mine did and sent 13 volts to the mpu and burned the clock up. jim at rottendog gives awesome customer support , he repaired it and paid the shipping to send it back to me at no charge. this is the second time hes fixed it and not charged me. anyway that's another post all together. good luck with your BK

I really cant give an opinion of the rottendog because ive only tried it in one machine, mine. and mine has other issues I think than the board itself. I need to replace some molex plugs and some of the plugs that goto the board itself. you will read mixed opinions on the rottendog board but I think its not the board but the machine its put into. I have had several issues with gameplay that will change just by me unplugging plugs and plugging them back in will most of the time fix the problem or make it different somehow. it is very nice not having 2 separate boards and also being able to put it in other games just by flipping dip switches and not having to have the actual game roms. I think rottendog makes a good product and has some of the best customer service ive seen. jim will take time to walk you through any diagnostics needed to fix your problem. im sure he got a few gray hairs helping me lol. an example of one problem I have is in switch test mode all the switches will register properly and when all the balls are taken out of the game I have no swtiches reading closed, which is normal, but when I play a game when I lock a ball in the upper trough it will not kick another one out. it just sits there. last time before the voltage regulator went out I had this problem and it was one bad connection on one of the plugs to the mpu board.