Lachlan Keown released a new version of his sprite editor for Windows. With AMSprite you can paint your graphics / sprites on a Windows PC and use them for your CPC productions, so it is perfect for cross-development. You can donwload it from the CPC Wiki article.
Changes in version 1.4:
- Included option to output mirrored sprites.
- Outputs hardware sprites in compressed format.
- Supports video import under 64-bit OS.