Hi Baihe,
Sorry you're experiencing this problem - actually we're aware of the issue and are actively working to fix it. In the meantime, you may "Skip" this registration step and then select Help: Register (not Register Online) from LEAP's main menu. Enter your registration information in the screen that appears and click okay. You should see a dialog that says "Thank you for registering". If a second screen appears asking you to enter your registration information again, simply click "Skip".
We'll keep you informed when the problem is resolved.
Best,
Taylor
UPDATE 7/29/2016: This problem is now resolved. Please download and install the latest version of LEAP.