The box pops up because it's trying to write the time and monitor status to a file so you can keep a record of the house decay to try and see when it will drop. I think this should happen every 2 minutes and is configurable.
I can't test on Windows 8 because I refuse to own it, you'll have to try and figure out why the "cmd" execution isn't writing the files correctly. The file is trying to be written to your c:/ as <shard>_collapselog.txt. Your loot profile is being written as c:/<shard>_lootfile.txt. If you can't write to your c:/ directory, then this is where the problem is probably at. For now, I won't support Win8 so you'll have to modify the script by probably removing all references to "c:\"