GeoEvent Processor, as an extension to ArcGIS 10.2 for Server, must be installed and run on an ArcGIS Server version 10.2.
When adding/updating feature services that are running on another ArcGIS Server, those Feature Services can be running on either 10.2 or a 10.1 version of ArcGIS Server. We do not support Adding/Updating features with an ArcGIS Server 10.0.
Hope this information helps,
Adam Mollenkopf
ArcGIS GeoEvent Processor for Server - Product Lead