I was sweating bullets for the last 30 minutes, I will have nightmares of unreal's UI widget blueprints for the next month, im still not 100% sure they will scale properly on different resolutions
Unless you need to graphics power of Unreal... Unreal is not the best for Jams. It's really tough to get a good web build using Unreal because they dropped native exporting support.
Unreal is a tool, make sure its the tool for the job.