Windows 10 / 64bit.
I got it up and running twice by uninstalling Knossos, then deleting everything I could find out of appdata\roaming and local and everywhere.
Now I have 2 tabs on Knossos front screen - retail and The Babylon Project which I installed. Media MVPs are in the 'install' tab now even though they weren't for the first run runs. installing them gave me trouble before; perhaps I should now since the game stopped running.
The retail icon on the home screen executed 19.0.0.0 twice as I mentioned but now just flashes with nothing running.
log.txt:
INFO:MainThread:launcher.main: Running Knossos 0.14.3 on PyQt5 and Python 3.6.8 (tags/v3.6.8:3c6b436a57, Dec 23 2018, 23:31:17) [MSC v.1916 32 bit (Intel)].
INFO:MainThread:launcher.main: OpenSSL version: OpenSSL 1.0.2q 20 Nov 2018
INFO:MainThread:util.call: Running ['C:\\Program Files (x86)\\Knossos\\7z.exe', '-h']
INFO:MainThread:integration.init: Activating Windows integration...
WARNING:MainThread:repo.add_mod: Mod <Mod "FSO" 3.8.1-20180725 (FSO)> is empty, ignoring it!
WARNING:MainThread:repo.add_mod: Mod <Mod "FSO" 3.8.1-20180924 (FSO)> is empty, ignoring it!
WARNING:MainThread:repo.add_mod: Mod <Mod "FSO" 3.8.1-20181111 (FSO)> is empty, ignoring it!
WARNING:MainThread:repo.add_mod: Mod <Mod "FSO" 3.8.1-20181113 (FSO)> is empty, ignoring it!
WARNING:MainThread:repo.add_mod: Mod <Mod "FSO" 3.8.1-20181114 (FSO)> is empty, ignoring it!
WARNING:MainThread:repo.add_mod: Mod <Mod "FSO" 3.8.1-20181218 (FSO)> is empty, ignoring it!
WARNING:MainThread:repo.add_mod: Mod <Mod "FSO" 20.1.0-20200614 (FSO)> is empty, ignoring it!
WARNING:MainThread:repo.add_mod: Mod <Mod "FSO" 20.1.0-20200613 (FSO)> is empty, ignoring it!
WARNING:MainThread:repo.add_mod: Mod <Mod "FSO" 3.8.1-20191223 (FSO)> is empty, ignoring it!
WARNING:MainThread:repo.add_mod: Mod <Mod "FSO" 3.8.1-20191228 (FSO)> is empty, ignoring it!
WARNING:MainThread:repo.add_mod: Mod <Mod "FSO" 3.8.1-20200107 (FSO)> is empty, ignoring it!
WARNING:MainThread:repo.add_mod: Mod <Mod "FSO" 3.8.1-20200114 (FSO)> is empty, ignoring it!
WARNING:MainThread:repo.add_mod: Mod <Mod "FSO" 3.8.1-20200119 (FSO)> is empty, ignoring it!
WARNING:MainThread:repo.add_mod: Mod <Mod "FSO" 3.8.1-20200129 (FSO)> is empty, ignoring it!
WARNING:MainThread:repo.add_mod: Mod <Mod "FSO" 20.1.0-20200206 (FSO)> is empty, ignoring it!
WARNING:MainThread:repo.add_mod: Mod <Mod "FSO" 20.1.0-20200209 (FSO)> is empty, ignoring it!
WARNING:MainThread:repo.add_mod: Mod <Mod "FSO" 20.1.0-20200412 (FSO)> is empty, ignoring it!
WARNING:MainThread:repo.add_mod: Mod <Mod "FSO" 20.1.0-20200420 (FSO)> is empty, ignoring it!
INFO:Thread-10:util.download: Downloading "
https://cf.fsnebula.org/storage/repo.json"...
WARNING:Thread-10:repo.add_mod: Mod <Mod "FSO" 3.8.1-20180725 (FSO)> is empty, ignoring it!
WARNING:Thread-10:repo.add_mod: Mod <Mod "FSO" 3.8.1-20180924 (FSO)> is empty, ignoring it!
WARNING:Thread-10:repo.add_mod: Mod <Mod "FSO" 3.8.1-20181111 (FSO)> is empty, ignoring it!
WARNING:Thread-10:repo.add_mod: Mod <Mod "FSO" 3.8.1-20181113 (FSO)> is empty, ignoring it!
WARNING:Thread-10:repo.add_mod: Mod <Mod "FSO" 3.8.1-20181114 (FSO)> is empty, ignoring it!
WARNING:Thread-10:repo.add_mod: Mod <Mod "FSO" 3.8.1-20181218 (FSO)> is empty, ignoring it!
WARNING:Thread-10:repo.add_mod: Mod <Mod "FSO" 20.1.0-20200614 (FSO)> is empty, ignoring it!
WARNING:Thread-10:repo.add_mod: Mod <Mod "FSO" 20.1.0-20200613 (FSO)> is empty, ignoring it!
WARNING:Thread-10:repo.add_mod: Mod <Mod "FSO" 3.8.1-20191223 (FSO)> is empty, ignoring it!
WARNING:Thread-10:repo.add_mod: Mod <Mod "FSO" 3.8.1-20191228 (FSO)> is empty, ignoring it!
WARNING:Thread-10:repo.add_mod: Mod <Mod "FSO" 3.8.1-20200107 (FSO)> is empty, ignoring it!
WARNING:Thread-10:repo.add_mod: Mod <Mod "FSO" 3.8.1-20200114 (FSO)> is empty, ignoring it!
WARNING:Thread-10:repo.add_mod: Mod <Mod "FSO" 3.8.1-20200119 (FSO)> is empty, ignoring it!
WARNING:Thread-10:repo.add_mod: Mod <Mod "FSO" 3.8.1-20200129 (FSO)> is empty, ignoring it!
WARNING:Thread-10:repo.add_mod: Mod <Mod "FSO" 20.1.0-20200206 (FSO)> is empty, ignoring it!
WARNING:Thread-10:repo.add_mod: Mod <Mod "FSO" 20.1.0-20200209 (FSO)> is empty, ignoring it!
WARNING:Thread-10:repo.add_mod: Mod <Mod "FSO" 20.1.0-20200412 (FSO)> is empty, ignoring it!
WARNING:Thread-10:repo.add_mod: Mod <Mod "FSO" 20.1.0-20200420 (FSO)> is empty, ignoring it!
INFO:MainThread:runner.run_mod_ex: Starting mod "Retail FS2" with cmdline "['-mod', 'FS2', '-parse_cmdline_only']" and tool "C:\Users\Heinrich\Documents\Knossos\bin\FSO-19.0.0\windows/x64_avx/fs2_open_19_0_0_x64_AVX.exe".
INFO:Thread-14:runner.run: Launching FS2: ['C:\\Users\\Heinrich\\Documents\\Knossos\\bin\\FSO-19.0.0\\windows\\x64_avx\\fs2_open_19_0_0_x64_AVX.exe', '-mod', 'FS2', '-parse_cmdline_only'] in C:\Users\Heinrich\Documents\Knossos
INFO:Thread-14:util.check_output: Running ['C:\\Users\\Heinrich\\Documents\\Knossos\\bin\\FSO-19.0.0\\windows\\x64_avx\\fs2_open_19_0_0_x64_AVX.exe', '-get_flags', 'json_v1', '-parse_cmdline_only']
INFO:MainThread:runner.run_mod_ex: Starting mod "Retail FS2" with cmdline "['-mod', 'FS2', '-parse_cmdline_only']" and tool "C:\Users\Heinrich\Documents\Knossos\bin\FSO-19.0.0\windows/x64_avx/fs2_open_19_0_0_x64_AVX.exe".
INFO:Thread-15:runner.run: Launching FS2: ['C:\\Users\\Heinrich\\Documents\\Knossos\\bin\\FSO-19.0.0\\windows\\x64_avx\\fs2_open_19_0_0_x64_AVX.exe', '-mod', 'FS2', '-parse_cmdline_only'] in C:\Users\Heinrich\Documents\Knossos