Partition Assistant (PA) main console means the main interface of Partition Assistant, when you launch Partition Assistant, the first window is the main console. PA main console list the disk and partition configuration, and you could right-click one disk or partition to do some operations, such as: resize, create, merge, allocated space, and etc. And you could resize partition directly, by drag the handle on both sides of partition.
Some situation that lead the operation could not be completed under the “Extend Partition Wizard” therefore, you could only resize the partition on the PA main console. (You could refer to “Error in Extend Wizard”)