Failed to load resource: the server responded with a status of 404 (Not Found) http://static1.scirra.net/arcade/games/3969/pathfind.js
Here are three different games I've tried with the same error:
If I download the capx for the last on it previews just fine in r123.2. My system is winxp/sp3
Here is a relevant topic where two other people are having the same issue:
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Moving to Website Issues, Tom needs to fix this.