It's a big subject, so best to send me some supporting source code that demonstrates it.
The custom separator bit needs some expertise in configuring and possible there are bugs too.
Send me your file so I can investigate.
info@adventuron.io
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You're welcome to the whole file, but perhaps have a play with it first. It's at https://warrigal.itch.io/igors-quest. Password is 'Fritz'.
You can certainly see some of the obvious things, including the separator bug on mobile phones. In the meantime, I'll experiment with image sizes and settings for the itch.io page.