There are modifications in the MIUI Rom that are not compatible with CM7, so you need specific kernels and ROMS. On other phones (SGS for example) MIUI and CM7 are mutually compatible.
Keiran, I would presume that it has some sort of recovery... if it's built from CM7, which does have one.
By the way, JasonStein, could you separate the "ROM builder" and the "Autoflasher" in 2 separate executables? When you're testing different MIUI builds, it's a bit cumbersome to have to go through the first steps again.
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