Are you using the latest version 1.1.2(1201)? Please click Global Settings and turn on Show FPS to check the version number.
Also, we hope you can click SKYBOX's Global Settings(the gear icon), click the BUG icon in the upper-right corner, and send us a bug report attached with logs? You just need to tick the "upload logs" box then send the feedback with the same email address.
After knowing what went wrong, we'll help you solve it ASAP.