I thought the APU was implied when i mentioned in the beginning of my post "Dual Graphics" and also mentioned the two GPUs. However, I admit I didn't know that and I followed the procedure you suggested. The fun fact is that it directed me to download the exact same driver as the one I had been downloading manually all this time. Same driver name, same size, even in the "Supported products" tab, APUs and Mobility Radeon support is included in the same driver. I was not shocked to find out that once I installed it the exact same boot problem came back... So I could tell as far as drivers are concerned, it's not really a big difference. Anyway, the frustration is still big with this issue..
UPDATE: I figured out that the boot issue occurs when I have the option "Enable AMD Radeon Dual Graphics" selected at the control center. When I checked on "Disable", the boot problem went away and it booted as it should. However, it can't play games like this, so do you think there is something I can do or just wait for it to be fixed?