If images are missing or not showing in your email signature when you compose an email in Apple Mail, before contacting Support for further help, please check the following:
Do you have "Load remote content in messages" ticked in Mail > Preferences > Viewing
Do you have the Message Format set to "Rich Text" in Mail > Preferences > Composing
When you installed the signature, did you copy and paste your signature from the Google Chrome browser, not Safari (see Before You Start section on the installation guide).
Images not showing in email signature settings preview
If images are not showing in the email settings signature preview area, (where you install the signature) this is normal. Compose an email and you will see the images.