An internal error has occured

I have my project almost finished. When I try to add a new element like a label or a button, I get the error "An internal error has occurred. Report a bug? ". I also have this error:

otes = Browser: Mozilla/5.0 (Windows NT 6.3; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/39.0.2171.95 Safari/537.36

foundIn = nb139f

faultData = com.google.gwt.core.client.JavaScriptException: (TypeError) : Cannot read property 'A' of undefined

projectId = 5135668264042496

I have to add that after this happens, the label or the button appears but its set of blocks doesn't.

I can build the project, can run the emulator and the app works fine. I don't have any warnings or errors and I've already changes browsers and restarted my computer.

Any suggestions??

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What happens when you back up a step and load one of the previous AIA files you made?

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If I load a previous version I don't have the error.

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So that tells you something you added is causing a problem.  Can you add things back tot he older version to bring it up to the current version?  Make an AIA file after each successful add, and you'll know exactly where you're failing...

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Ok Enis, thank you very much for your help!

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Ditto Carlos!  Read my tips... you might be getting towards the size limit and that's why you're having problems... that's just a guess.

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this looks like a App Inventor bug.  Unfortunately, it's one that might be hard to find.   Could you send us the AIA file together with a description of what needs to be done for elicit the error.
It might take a while for us to look at this, but we'll try.

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