http://www.mediafire.com/file/b4gkkzpaichbl25/file.rar/file the files you requested from me
Still unable to experience a crash myself. I am sending this to someone else, with an AMD chipset to see if they have any problems. I also have one other machine I can try, with a different operating system (mine is Win7) that I will also try when I can. So far, I have not been able to get a crash to happen. I also don't see any crash-related problems in the log files.
If my attempts to obtain a crash don't work out, I might need you to create a Windows Crash Dump file. I will let you know if I need that and how to make one.
I am still waiting on that other person to try your fort/boarding save on an AMD machine. But, I did try several times on a Win10 machine, using a standard Intel video chipset and did not have any crash trouble. So your problem is still a mystery because I've been unable to reproduce your colony battle problem on any machine I have access to (Win7 on Intel, WinXP on Intel, Win10 on Intel), even with your save, or other attempts I've made in my own games where I've sacked various towns.