I would flip the gear over so the side with the slim boss is uppermost.....otherwise the finish on the bottom will be not very good as the first layer of the main gear wheel will be printing over fresh air!
If you previously used a split process, it has an issue where it remains "Start printing at height"
So go to the advanced tab, and make sure that box is not checked. I noticed this happened and
my printer was starting the print at 1mm because of previous settings, bypassing the raft layers