The error you're encountering, "Update file integrity check failed," suggests that the update file for Spine 3.8.95 does not match what the launcher expects. This can happen if the file is corrupted or if there is an issue with the download process. Since you are using a Windows VM on a Mac with Parallels, ensure that your VM is configured correctly and that there are no network issues affecting the download. Additionally, try downloading the update again to see if the issue persists. If the problem continues, consider checking for any software that might interfere with file downloads, such as antivirus or firewall settings.