1. After installing and testing this component I found the info windows it generated were showing up empty in IE and not at all in Firefox. They displayed perfectly in Opera however.
The answer to this is to create a text file containing...

AddType text/xml xsl

...then renaming the file .htaccess and uploading it to the /components/com_google_maps directory of your site.

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2. It seems a recent version (at time of posting) of this component was supposed to do UK Geocoding. This doesn't seem to work, and actually hangs the system when you try to create a new marker.

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3. The component author notes that map loading will slow down significantly if a map has more than 200 markers. This is caused by the Google map API itself.

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4. It is possible to set this up so that the info window shows certain fields depending on logic, using the construct. See here
I'll add more here as and when I test this out.

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