I've been working on a personal mod for me and my buddies, so this error might not occur with other mods (probably does I'm sure); I haven't had time to check it out. Anyway, the mod was obviously for Sins 1.13 using 1.1 ForgeTools. I uninstalled Entrenchment in order to mess around with the modding in 1.13. I had the mod set to load on startup. I forgot to turn this option off before I reinstalled Entrenchment, and the result was that the operating system would go to a frozen black screen; nothing loads up at all (no intro sequence). I guess I could have avoided it fairly easily by turning the option off in 1.13 before reinstalling Entrenchment, but it seems like something that could be fixed fairly easily by just having the Entrenchment installation process return the "load mod on startup" option to "off". Otherwise you have to remove the mod from the "Mods" folder manually. Might save some people major headache if they don't realize what's happened!
Great game guys, keep up the excellent work!