Your log contains:
Another process has modified Spine's files, please reinstall.
This means you must have some other software on your computer that is interfering with Spine. Once that happens, Spine can crash for any reason, there's not much we can do.
Please disable any antivirus or similar software. You may need to uninstall some software, such as Comodo Firewall, because it will continue to interfere with other programs even if you "disable" it.
Also, your Spine launcher is 4.0.37
. If you download and reinstall, you'll get a newer launcher, 4.0.48
.