Hi Thomas,
Icy provides some methods to make the image acquisition easier and return image in the appropriate format for Icy but there is currently any documentation to use it.
You have to look in the sources and in the javadoc from the original
Micro-Manager plugin for Icy.
You can extends MicroscopePlugin or even MicroscopePluginAcquisition so your plugin will automatically load the micro manager engine at starting.
You can retrieve the Micro Manager core by doing :
MicroscopeCore core = MicroscopeCore.getCore();
And you have some classes utilities as
ImageGetter for easier acquisition or
StageMover to control XYZ position of the microscope.