Yes, Sat2Chart is still alive and well, and still being updated. I don't know if Paul still watches a GE2KAP group on Cruiser's Forum anymore, but he's active on the GE2KAP FB group.
The "overlay GoogleEarth on OpenCPN" feature has just been removed. It hasn't really been useful for quite awhile because GoogleEarth took away the interface that GE2KAP was using to do its magic. Everyone is now using SAS.Planet as their source of imagery, because there are 4-5 sources of
satellite imagery there and 2-3 charting sources.
You can download a compatible version of SAS.Planet from the download link that Stingo provided. It's a little fiddly and not well documented (Paul's
documentation in Sat2Chart is the best source). But brilliant and easy to use once you get the hang of it.
Sherry
s/v Soggy Paws
currently in Malaysia