link and synchronize Synfire with Cubase using drones and how export your composed music.

Cubase has some builtin VSti like Halion Se ..can i use this in Synfire ?  

I did not succeed in loading any of the Steinberg plugins into the Synfire Engines or Drones. If I try to load Halion Sonic SE I get the response that it could not be loaded. Don't know what's the problem with them. They also cannot be loaded into Finale, btw. Maybe because they are VST3 plugins?

Have the same issue with the ableton native instruments, I use midi drones or virtual midi cables to get round the problem.

I don't know if they are v3 and if synfire supports v3 vstis. Also are you sure they are licensed, and built for use outside hosting in cubase? I've had vsts that came with sonar that complain if I try load them in another daw and probably hoSting them in synfires drones would count as a non cubase host.
Midi drones or virtual midi cables are the way to go in these cases.

Is it possible to get a videotutorial for using SFP with Cubase 6.5 ?

I can not create a video at the moment, so I try to explain with some screenshots the setup for the routing from a Synfire MIDI Drone to a Steinberg plugin which is directly hosted at Cubase.

The term "MIDI Drone" means that the Drone does not host the VST instrument itself (what's the usual way to use the drones but does not work for Steinberg plugins, because for some reason they can not be hosted at the drones). A MIDI Drone only receives MIDI data from Synfire which then can be routed to a VSTi, which is directly hosted at Cubase.

To do that, use the following steps:

1. In Cubase load the "VST Instrument" CognitoneDrone (picture Cubase_Loading_Drone.png). If you are asked, if you want to create a MIDI track for this "Instrument", you can select "No" because you do not need a separate track for the Drone.
2. Create a new instrument track. Choose the desired VST instrument, for example Halion Sonic SE and load the desired sounds into the VST instrument.
3. At the input of the track choose "1 - CognitoneDrone - Midi Out". The little loudspeaker symbol at the track inspector or the record button next to it must be switched on which means that the track will accept MIDI input data (see "Cubase_Track_Setting.png").
4. In Synfire create an instrument, select the instrument tab at the inspector and make the settings  shown in the picture "Synfire_Drone_Setup.png": Choose Type: "Private plugin", Port: "DAW2: Cubase01" (or similar), select "MIDI Drone" and make the desired instrument settings (channel, program, ...)

It seems to be not so complicated ..but this reminds me on the HN2 MIDI sound assigning.. 

Of course you can also still use the setup, which you know from HN2 (MIDI loopback driver). This was not so bad, IMO, and I actually still use this kind of setup sometimes.

But using the MIDI drones instead has the advantage that you can drag the MIDI data directly from the drone and drop it at a track at Cubase. That's a really cool thing. ;) No need to export MIDI files from Synfire and reimport them into Cubase anymore.

If you want to import into sf and have it play exactly the same, import as static notes. I believe yOu can also get your daw to play the notes into synfire if you prefer to use your daw to edit.
Personally I don't see any point to entering notes into sf using a full notation view, if I was musically gifted enough to be able to compose with a notation editor, why would I need to use synfire? However, I do see the advantage of installing lillipond so that once I've composed something in synfire it can be output as proper notational score, this is something synfire already supports.
Andre has hinted that the phrase editor does need some work to make it more useful when creating phrases from scratch and I look forward to seeing these, but if it were a full notation score editor, I wouldn't be using it.
I have to hear the music to tell if I like it, I am unable to judge what sounds good just by viewing it in a notation view, although a lot of people would disagree with what I consider good!

I personally would like to see a traditional score and edit that way.. but it's not a big deal.. I taught myself about 5 years ago using Logic.  Now I sometimes find it faster to build an arrangement, correct and enter phrases and parts, using the score editor.

Right now, SFP has enough issues going on with it,  a score editor can wait.  We really need to get all the users here up to date with all the various aspects.  It seems only a handful post here.  making me wonder if other owners, are too overwhelmed to ask or post things here. 

I have  imported my Logic songs static and rewired them together.  I shut off the same Logic tracks.  About 20 mlliseconds is as close as I can get the two apps.. So it's a little sloppy, but by shutting off Logic tracks, I'm directly hearing SFP and seeing a score in Logic.

I'll create a new part in SFP and immediately export out/and import into Logic.  This has been a helpful.  I'll look at a track and make note of where I want it to get busier, sparser, and go back to SFP and alter the track, then export back into Logic.

Since I'm using MIDI hardware, the clones don't work for me. 

After several months I'm beginning to think that I want to use SFP as a stand alone application.  Which would mean I need access to see individual note list editors and hand enter  CC and sysex data, that SFP  is not capable of.  

I would love to see the accompianment page to also double as a mixer - to quickly edit parameters, rather then jump around containers, and  edit individual tracks. 

SFP is great.. I anxious await to see how it grows..