We are often asked "How do I create a custom size layout in RelayThat?"
This is often because a user wants to create a specific size for their website theme header or post size like the one shown here.
Unfortunately, this is not currently possible at this time due to the complexity of our resize and remix layout library.
If you need a specific size the best option is to let us know the size you are looking for two reasons.
We ARE continuing to research this challenge and hope to provide many more size in the future. It's unlikely that we will ever be able to offer completely random size like 491x303 but we also don't find that many of our users need such specific sizes like this.
Our apologies if this cause any inconvenience at this time.