I just had a .capx crashed with this error:
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Error loading project
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Failed to open project '\\?\C:\Users\Morphine Central\AppData\Local\Temp\cap1O1VSW\Game.caproj':
behavior name already exists in object type
Under element: c2project \ families \ family \ behaviors \ behavior-type
Line 471, column 17
The file may be invalid. Try checking the file in a text editor (projects are saved in XML format).
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OK
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How to reproduce:
1 - Create an sprite, give him a behavior.
2 - Create a family, put the sprite on it.
3 - Give the family the same behavior, with the same default name.
The behavior in this case was Rex_MoveTo, I?ve solved the problem by editing the sprite?s behavior name to MoveTo2.
The likely reason the names where duplicated was because I?ve copied the sprite object from another .capx.