Use the stretch button when configure timer can stretch the timer to adapt to different size screens.
No, there is no limit for timer and there is also unlimit of impressions.
To adapt fonts to mobile device, you need to use the preset designed for mobile, and you can select this in timer preset configuration.
If the page you want to navigate to is in the same site, you can find the page url at the SEO basis section of the page setting when you edit page in wix editor.
There are two situation the countdown timer will disappear: when the timer countdown to zero or when the timer is not start in the repeated mode.
