MACD_Momentum: What's the problem?

Hi

I have found this indicator Attachment
some time ago and find it very useful.
Unfortunately it only works on some pairs and is not showing on others.
Could by any chance some gifted coder take a look and find out what is wrong with it?


Here is a screenshot of a chart where it is displayed without a problem:

Attachment

And here is a screenshot of a chart where it not displayed.

Attachment

If anybody could help me with this,
It would be very appreciated.

Thank you!