O Rly? Well, you could download a program like VDOTool and modify the fan settings, the 3D fan settings should always be on 100% 2D will be lower, just up that to like 100% Should work. I have both my 3D and 2D on 100% and my computer never heats up. (as far as i know)
I have stumbled over what seems to be a solution (finally). After serching on google with the keyword 'sysdata.msi' I found a forum where someone was having the same problem, not with WC, but with Call of Duty, after searching the thread I found a suggestion to delete C:/Documents and Settings/ <youradminnamehere>/Local Settings/Temp, and also to un-hide the local settings folder, and restart the computer reseting the Temp folder and Local settings.
What blew me away was, it worked , I couldn't understand how this one folder could possibly have an effect on WC:WE terrain editor (@_@)
I'm happy that I can finally continue mapping after what feels like years.
Thanks all for your suggestions, It seems this experience, for me at least, has highlighted the fact that computers are staggeringly strange and unpredictable machines, to think I was about to kick my computer to pieces .
I do know this - xenforo dropped the ball by not keeping the vbulletin reputation comments as a feature. The loss of the Reputation comments data when we switched to Xenforo really was the death knell for the site when it came to all the users that left. I know I missed it so much and I got way less interested in the site when that feature was gone and I run the site.
I'm on a page about incorrect corrections, and spent the better part of like two hours trying to get someone to understand that -5^2 = -25, not 25, and then that post had comments get reposted because that group is self sustaining, and that person was in turn trying to explain what I just explained to them. And I'm taking that as a victory