From the plugin inline help:
" Align RGB planes v1.7 by G.Landini Changes the alignment of the RGB planes independently.
Red Green and Blue checkboxes switch ON and OFF the planes and undo the alignment since last plane change. Note that when switching planes, the portion of the previously edited plane left outside the image frame is lost. Rotation, Width and Height changes are interpolated (so there is some loss of sharpness) and do not retain the image portions outside the image frame. You can use the Resize2Rotate macro to avoid losing any image data.
The Rotate, Width and Height sliders set integer values, but fractional values can also be typed in the entry boxes. Just make sure you press [RETURN] after the number is typed.
The Revert button works only with single images, not stacks.
Note: When using stacks, 2 buttons [< Prev] and [Next >] are added to the panel. Do not use the slide bar in the stack window, but use those buttons instead."