Does it support IMG files?

[剑气冲天]

BTW, what distributions only support img format (without ISO file)?

Most of the chromium OS images are packed as img or bin, because there are more than one partitions in it. You can use FydeOS as a reference.

FydeOS的功能特性可以说是目前ChromiumOS目前绝对的第一了，为数不多走在了世界前列的国内团队，个人非常期待后续发展。