zhulei We're sorry to hear that you're having trouble, but unfortunately, we can't fully understand the issue without more details. The spine.log file you attached only mentions that you tried to download Spine 3.8.99, but it doesn't record any startup errors or other details that would help us identify the problem. Perhaps the download took too long, preventing you from launching 3.8.99? Please provide more details about the issue you're experiencing.