Began work on the first beach level today. Screenshotted from Amiga Forever, set is as a background image with reduced brightness for ease of use as a template, and began placing the tiles manually. Here's how it's coming along so far. This is about 15 minutes' work:
(With background template image)
(Without background template image)
I anticipate that it would take me several hours to figure out how to work with the original tiles / .dat level files, particularly since they aren't already in some accessible format and I'm getting sass from Windows when I try to even get started, so I'll continue with the manual work for now. It will be slower overall, but at least it will definitely get done.