Here's my attempt (HD bump it up) ... English ... but Kiwi, who lives in Oz, with a good stint in the UK, otherwise well travelled (and resultantly weathered)

NOTE: I recognise there's a few pop/cracks in the audio on the video. This is not typically an issue. For now I'll put it down to the resource load imposed by the recording software.
 
 VoiceMeeter / Sonar setup for live video commentary:
http://youtu.be/L4qH4bAueIY
 
 

Thanks ShellstaX. I'll give that a go later today.

Bapu,
 
Why are you looking for ways to independently record audio while demoing something in Sonar? You have an RME, right? You can just use RME DigiCheck which comes with your device to record the audio using the global record selection.
 
Do your screen capture with any screen capture software you like. Then import the audio captured with Digicheck into Sonar and import the video you captured into Sonar. If the video software has ANY kind of audio capacity (you really don't care if it's any good) you can capture a clap or something to align the two audio recordings.
 
Ewe no @ DigiCheck, rite?

gswitz
Bapu,
 
Why are you looking for ways to independently record audio while demoing something in Sonar? You have an RME, right? You can just use RME DigiCheck which comes with your device to record the audio using the global record selection.
 
Do your screen capture with any screen capture software you like. Then import the audio captured with Digicheck into Sonar and import the video you captured into Sonar. If the video software has ANY kind of audio capacity (you really don't care if it's any good) you can capture a clap or something to align the two audio recordings.
 
Ewe no @ DigiCheck, rite?

Nope never heard (see what I did there) about DigiCheck. Is it installed with drivers? Is it an app? Is it part of Total mix? 
 
 
Help a bruthuh out.

http://www.rme-audio.de/en_downloads.php?page=content/downloads/en_downloads_driver&subpage=content/downloads/en_downloads_digicheck
 
Try this link.
 
It's a super cool tool. You've got some reading to do. It has an awesome EBU meter, direct recording from the interface (that records all audio to a single file on your machine until you save it to separate files). Really, digicheck does so many cool things I just recommend you read the help file.
 
In this video you can see me using 3 instances of DigiCheck.
https://www.youtube.com/watch?v=pmTb8XqawP8
I'm also using another instance to record my voice for the video.
 
You might keep in mind if you're aiming for posting to youtube that you may find yourself with limited video durations. In some cases 15 minutes. I don't know if they limit or not b/c I don't normally attempt a video more than 10 mins.

Geoff,
 
Thanks for the tip.
 
So, I got DigiCheck to globally record. I now understand how to save the recording. 
 
The "Action" product will save my 30" 2560x1600 display.
 
So far so good.
 
What I'm unclear on is how to sync the audio and video since they are started at different times.
 
You said "If the video software has ANY kind of audio capacity (you really don't care if it's any good)". But isn't that the rub? Since I only use RME (in ASIO) on my DAW, no screen capture program has yet to capture ANY audio for me.
 
Maybe I'm not reading what you wrote correctly.

Well, I use MS Expression which is old software that you can choose the audio input for (and the rme inputs show up). I don't think they still support or sell this software.
 
I can also select and record RME inputs with CamStudio. I can select Audio > Options and pick an input from the RME.
 
Alternatively, if you really can't capture audio with the video capture, you could sync up a mouse movement (like move the mouse to the lower right hand corner twice and tap the desk each time and sync the taps to the mouse movement.
 
For me, I always capture the audio on outputs 7+8 as the stereo pair for the recording. I also send the Sonar Mains to 5+6 (and also route to 7+8 so I can hear them using totalmix). Then, I set 5+6 for loopback and record 1 (my talking), 5+6 - full strength Sonar Output so you get real time fader movements and stuff the way they happen), and 7+8 (which has Sonar out mixed with my vocal as I heard it during the performance of the video recording).
 
When I'm done, I can input as separate tracks
- the stereo pair output from Sonar (5+6).
- My voice
- the mixture of my voice and Sonar (7+8)
- The stereo pair as captured by the video capture.
 
Now, DigiCheck + Sonar + Video Capture device all linking to your RME can get interesting, but in my experience DigiCheck always wins with the smooth recording. DigiCheck has never enabled some other audio program to mess up the DigiCheck recording. On the other hand, sometimes I get pops and clicks through the Microsoft Expression input.
 
See this video...
https://www.youtube.com/watch?v=d6Lqj6-j05Q
 
You can see me start talking - before I remember to start recording with digicheck. I notice at 40 secs that I'm not yet recording with digicheck and you hear pops and clicks for those first few secs then no more pops and clicks b/c digicheck is on.

As an addition, it may be that the screen capture software that I use doesn't use ASIO. I don't know. There's no setting for it. But the RME does show up so I can select the inputs. This may be why the screen capture audio skips and pops a little. It may be that when recording both using ASIO and some other stream method that the other one sometimes faults. I'm not sure.

Bapu, not that you would need this help (I'm guessing) but if you happen to be making a mobile recording with a laptop and want to capture the recording with digicheck, I think it can enable you to record more tracks at a higher sample-rate than Sonar could support with a given hardware limitation since Sonar writes them as distinct tracks as it goes. The drive load using digicheck seems very low - since it only writes one file. I'm only guessing, but I do usually use digicheck for capturing field recordings where I'm not having to use anything but the RME.
 
There's also an Ipad app, fyi.
http://www.rme-audio.de/forum/viewtopic.php?id=18787
 
Oh, and the last field recording I captured I used Linux UbuntuStudio and the RME in class compliant mode. It was not a very important field recording and I just wanted to try it out and see what I learned. The biggest lesson learned was to zoom out the Ardour track view so I can detect overages/clips. I was zoomed in too much and didn't notice an occasional clip on an input that came off an external pre. Since the RME hardlimits clips, the recording was still definitely usable, but that was what I learned.

I started Action then started Digi then started SONAR.
 
Started my song. For this test I did not want to do voice over. Played the song for about 30 seconds.
 
Stopped SONAR. The Stopped Digi. Then stopped Action.
 
I can play the video (saved in AVI format) in WMP.
I can play the audio in WMP.
 
Open SONAR, type V and then File->Insert->Video. Select the saved video. I get a tab in Multidoc (the only one) that declares it's a Video. The tab is black and has the "clock" in red at the top. I have a new track that is labeled "Video" (looks like an audio track to me ).
 
Having never brought a video into SONAR I'm only guessing here but when I press play I was expecting to see a video. Nope. Just the "clock" changed with the passage of project time. The tab stayed black.
 
I guess I have even more reading to do about video in SONAR.