If the CRM Checkbox in the compose window is not allowing you change its status, ensure that it is enabled in the Extension Settings.
Click the Bananatag button at the top your browser extension, then select Extension Settings:
Make sure that CRM Integration is set to Enabled:
If you're experiencing this issue and this is already enabled, try disabling it and re-enabling.
Once this is done, you should be able to click the CRM box in your messages and use this feature as expected.