As it stands now, an administrator on a server can not spawn in illegal blueprints. This is a bit of an issue for people who would like to run events, say with spawning a POI manually on a planet that has been depleted of POI's (since there is no respawn mechanic at the moment) or even some interesting custom BP's that use illegal blocks (I won't go into detail here). I suggest allowing admins to send illegals to the factory OR even just allowing them to instant complete a BP with out having to send to factory say by the GroupName or BP Name. This would open up an entire world of ability for servers, as well as help combat the need to wipe worlds over an over on busy servers.
This is the only way I'm aware of to do that and it isn't something built into the current rev. The blueprint needs to be saved from the Creative game and made available under Contents/Prefabs Code: var entityId = modApi.ClientPlayfield.SpawnPrefab(prefabName, pos);