the most likely reason is that you're WoGifying a map with internal ERM scripts and you're getting conflicts. or you're playing a map with bad scripts. or you're using a previous version to WoG (like 3.57f) to play a map from a later version (3.58f).
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like i said then, probably conflict with wogify scripts or bad internal scripts... unless you've modified the map somehow. if you change/move/delete a hero/monster/obstacle/whatever that was to be affected by a script later in game, when the script runs and doesn't find the right object, you'll cause all kinds of errors.
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