Not really, unfortunately. The HTML width attribute it always my override for sizing since the CSS you mentioned you're already trying to use isn't working.
Do you have to use CID images? There's an old SendGrid article on embedding images that goes into why it might be a bad idea.
Outside of that, try this on your image tag:
<img alt="" src="http://placehold.it/1600x800" width="80" border="0" style="display: block; max-width: 100%; min-width: 10px; width: 100%;">
The width attribute of 80 should stop it scaling beyond that, then the inline styles take care of it being responsive but forcing it not to go below 10px wide - adjust to taste.
Started a new discussion: You should probably test your emails in IBM Notes 10...
The Litmus Community actually has a great job board! You can check out all of the positions here, I think there are a few for UK companies. You can also follow new listing on Twitter, too.
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Mind emailing our support team at hello@litmus.com? They can help you out.
Hey, Veronica! If you need some help, you can always reach out to our support team at hello@litmus.com.
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