Hi Jonathan,
Sure! Sorry about that, I thought the attached log covered most of that info.
I am on 4.4.3 binary from the launcher.
I get the error when I either click Launch from the editor some way through the cooking process, or when it cooks through cook/package the project. The cook fails and the output log contains what was in the previously attached log. The editor doesn’t crash or anything, I just cannot continue the cook process.
I’m really unsure of what caused the error to start showing up. I’m not trying to build for a new platform, nor have I added or enabled any new plugins or libraries. The only changes I’ve made would be code and content. I’ve both added and changed some code, blueprints, meshes and materials.
I was hoping you might have some suggestions or likely causes so I could try and narrow it down. Or what ExitCode 25 means in “AutomationTool exiting with ExitCode=25”
Worst case I can try reimporting content into a new project to see if I can find the specific point of failure - I was just hoping there might be some common causes for this type of error that I could look at before I did that. 
Thanks!
Simon