I run it on win 7 64-bit, which is pretty similar to 8 so it crashing like that is very strange.
Try turning off any antivirus you may have and then try to run it. There's been issues with AVs in the past causing crashes (sometimes they just see a program downloading stuff and freak out, causing a false negative, or otherwise just mess with the process) so they can be an issue.
The official updater is very old code so maybe something changed in Win 8 that is just not happy with it. Give
Landiin's EQ2MAP Updater a try if turning off your AV doesn't work, if that doesn't work then there's not much left options-wise.