Troubleshooting widget habpanel

I try to use the Meteogram binding in Habpanel, but all i get is a “broken” image…

I have tried to find out how to enable log/“other troubleshooting” for an widget in habpanel.
Do anyone have a good side for the general topic “troubleshooting of widget”?

Or perhaps even better know what my be wrong with the Meteogram?
I have filled out my API key, and set values on all the configuration parameters…

Best regards