Ohh, you made it! Congratulations! It's definitely possible to get the coin without the secret bombs, a diagonal bomb could break the rock in a similar way.
Also, I'm surprised since the secret level is supposed to be the hardest - the hard part is to break the rock in front of the exit.
The cursor blocked by the big wall is because of how flames were coded. They stop spreading when they reach a "Region 1", which is the same used to block the cursor. I changed the flame behavior in the later versions, but I forgot to remove the Regions from the wall in the middle.
