For show disks temperatures you must run CrystalDiskInfo on the background. You can give it here. But it is not enough. You must setup CrystalDiskInfo properly. First go to Function -> Advanced Feature and check Gadget Support. See picture 1.
Choose refresh time. Go to Function -> Auto Refresh and select desired time to refresh. If you select "Disable" temperatures will be not refreshed. See picture 2.
When you add new disk you must press F6 button for quick rescan. Drives Monitor show this disk immediately, but CrystalDiskInfo no. See picture 3.