I would, very strongly - almost command you to take a look at TileD - its a clean UI, fast and saves into Base64, or CsV based XML files with buckets of support and such an easy format to implement its probably one of the easiest standard to work with ever, and I'm dead serious there.

If you want code in pure pascal, I had to write a loader for CSV based TileD XML files thats open source under prometheus which I can post for you if need be...