So yesterday Unicorn was wondering if he could use Tiled (http://www.mapeditor.org/), with the CE C toolchain. Tiled is a really advanced tilemap editor and creator that can make tilemaps super quickly and easily, but adding plugins and stuff didn't seem to be quite right. ConvTile can take the .csv files exported by Tiled and convert them to be usable for creating your tilemaps. It also supports compression of tilemaps as well to further reduce size.

You can learn how to use it here:
http://ce-programming.github.io/documentation/tutorials/c/tiled-tilemaps/

You can find the source here; keep in mind it is already a part of the CE C SDK now, so no need to download anything.
https://github.com/MateoConLechuga/ConvTile
https://github.com/MateoConLechuga/ConvTile/releases/latest

It's not something particularly difficult to convert, but it's nice to have a quick tool for those small things.

Yep, it's true. Kind of nice to have compression though and it saves one extra step.

Great tool! One bug report though: running "convtile" from the command line crashes the .exe file, although the readme says that <output name> is optional.