I used a baking core for the first time, making a 1/2 soccer ball cake for a client.
After I took the cake out of the oven and let it cool a bit and had removed the cake from the pan, I decided to take the core out so the centre could cool faster. Big mistake! No sooner had I removed the core, and the cake feel into 4 huge parts! This was a very busy week for me (cake/cupcake-wise) so the last thing I wanted to do was waste time (and money) making another cake ... but I did.
Waited until the cake was completely cooled, THEN removed the core, and the cake from the core to fill in the hole.
Morale ... Don't rush. You're just going to have to do something again.
P.S. GF got a nice bunch chocolate cake parts for free. Her kids like my mistakes.
Well, atleast it didn't go to waste!