Yes, unfortunately parts of it rely on the 'route' hook utilized in pagehandler hijack, so they are incompatible currently. The problem is actually with pagehandler hijack, not this.
If you want to try to make them compatible it's a case of needing to trigger the route plugin hook with the original parameter while pagehandler hijack has control. For example if you renamed groups to clubs, then in the hook for 'route', 'clubs' you need to translate clubs => groups and re-trigger the hook with 'groups' instead of 'clubs'.
@Jose - I just re-tested that scenario, and the non-admin user could create subgroups. Tested both with the transfer of the top level group, as well as the transfer of a subgroup. You'll have to provide me with more information. Are you using group_tools to perform the group ownership transfer?
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