BUT -- if you use FULL ACCESS instead of Impersonate, the current download-able version works like a champ for this.
To try this out:
·        Provision a service
account (say, "exsu") that is NOT an Enterprise Admin
o   Set impersonate RBAC for that account
§  new-ManagementRoleAssignment -Name:_suImp8Exsu
-Role:ApplicationImpersonation -User:'exsu@cod.sumatra.local'
o   Try to do an insert for a user AND
o  For resources "cr101b" or "room 222"
Results should not be good, but NOW....
·        
Add fullaccess to
that service account
o   Get-Mailbox -filter {isResource -eq $true} 
-resultsize unlimited | add-mailboxpermission -user exsu -accessrights
fullaccess   -InheritanceType: All
o   Add holidays for that room

 
