I gave it another go last night and I can only say it would be a nightmare live. 
But I was using standard projects. I guess you have to make stripped down simple projects to use it smoothly. I had all these effects and VST GUI's  popping up everywhere. And none opened on my second monitor where they normally are?? The screen behind the playlist was a jumbled mess.. what's with that? I closed the playlist and my projects then opened normally without all the GUI's. No way I'm using buggy software live. 
 
Other than my desire for using midi to change my hardware effect processor there's nothing wrong with Win Amp. It's solid. I've used it for over 12 years now and it never crashed or stalled. I will look into a midi foot controller instead. 
 
I really don't excpect them to do anything with the playlist. It is what it is. Sonar does many things real well. We can't expect it to do everything. I'd rather special software that was optimized just for live. Forte is a good example for playing soft synth live. 
 
 

Cactus Music
I guess you have to make stripped down simple projects to use it smoothly.

I reckon that's the key to make the current play list feature work nicely. We've been using it live for about half a year now with X3e and it does exactly what we need it to do: change mixer scenes, change external FX via MIDI, provide up to 8 audio (!) backing tracks routed to different channels on the mixer, plus a count-in using WAV files for 1-2-1-2-3-4 (which is a bit funny but great when the crowd gets noisy!) ... so the set-up is simple - and we do not use any plug-ins at all (all FX is either bounced to tracks or applied via the digitial mixer)

When working on new material we have an additional 24 audio tracks in the project to be able to multi-track new arrangements - but live we go with clean smaller projects i.e. all unused tracks are all archived for the live performance so that they don't interfere.

Anyway, it took us a lot of testing and optimising to arrive at this rather simple project set-up (we built the entire set-up from scratch 4 times, each time simplifying something to get Murphy's law out of the way) ...
 
Plus it requires an SSD to have smooth loading of the next song in the background while on the current song is still on ... but now it enables us to change the playlist on the fly and quickly choose between auto-play (e.g. wait for 5 sec) or wait for key-press ... and handles everything we need automatically ...

Now, improvement can always be made, and I would opt for the following ...
... a better way how opened projects are displayed (currently they open in a funny way which is not the last view it was saved with) - best would be exactly as saved, with an option to open minimized ...
... MIDI keybind start - stop - next (currently this can only be done via keypress on the laptop keyboard)


Ideally, I would like to see it work with the matrix (triggering matrix fields being tied to MIDI commands) for both MIDI and audio clips but we are not there yet ... the functionality is all there, but I will need to invest quite some time in testing (and probably again simplifying) to make that integration safe enough for me to take along live ...
 

MIDI keybind start - stop - next (currently this can only be done via keypress on the laptop keyboard)
 
I use a usb foot switch which can be assigned any keys. 
http://xkeys.com/XkeysFootPedals/index.php
My review: 
https://www.gearslutz.com/board/reviews/923689-p-i-engineering-x-keys.html
 
So controlling playback with that works great. 
 
Glad to hear that it wasn't me that screwed up with the weird way projects open...
I'm planning on getting a Behringer Xair 12 or 16 digital mixer in a few months and this would be why midi control over effects would be cool. 
 
By the way, why do you find you need 8 raw tracks? I would think you could get by with less. 
I'm planning on 3
Stereo track of drums and keyboards
mono track of bass which I send to a bass amp. 
 
 
 

That's really the only fix I need, have the projects open the same way you last set them. That doesn't seem like it would be a major task--any hope of getting this added to the next update?

Cactus Music
MIDI keybind start - stop - next (currently this can only be done via keypress on the laptop keyboard)
 
I use a usb foot switch which can be assigned any keys. 

 
I was actually thinking about something like that, especially since I used to carry around a much larger FCB1010 just for play - stop - next in the previous setup we used ... but then I discovered the play list options to continue with "wait for x secs" or "wait for keypress" and now we rearrange our setlist to have blocks of 4 - 5 songs which run consecutively by itself ... which turned out to be really nice as it means hitting the space on the keyboard only once in 15 minutes, about 3 or 4 times during the entire set and then forget about it, just groove along :-)
 

Cactus Music
 By the way, why do you find you need 8 raw tracks? I would think you could get by with less. 
I'm planning on 3
Stereo track of drums and keyboards
mono track of bass which I send to a bass amp. 
 

We have 4 man line-up (classic rock band) but use all sorts of synths to fill the background in the studio recordings which we don't want to leave out completely when playing live ... so it's mostly the less obvious that adds to the atmosphere and mood which comes from the backing tracks (well, we actually had a 5th guy to take care of that but he got bored of playing so little he quit ... and was replaced by Sonar) ...
 
Anyway, 3 reasons we use 8 tracks:

• 8 mono channel is what we could afford to have sort of reserved on the digitial mixer for "cheating" ;-) with the playback tracks ... which gives us up to 3 stereo tracks plus 2 mono tracks for the playback, which we usually split into "Synth Hi", "Synth Lo", "Back Vox" in stereo plus click track and piano in mono ... sometimes we merge the synths to one stereo track and use the other stereo track for an extra guitar...
• set-up is really easy as we take bounced busses from Sonar and add the WAV files to the live set-up...
• instruments from playbacks are on separate channels, giving you full control over the mix in the digital mixer i.e. they can just be mixed as if you'd have a person playing it ... in fact, we had a gig with a piano player so we just muted the piano playback on the mixer and could use the same set-up as always ...

So yes, we could live with fewer tracks ... but the laptop easily handles 8 tracks, it means less work to set-up and much more flexibility for adjusting the mix to the venue ...
 
edit ...
PS: the combination of a digital mixer and Sonar (i.e. switching mixer scenes on a song basis using MIDI prg chg from Sonar) gives you endless possibilities regarding setup... you could use a different song template and mixer scene for each song, but you DO NOT want to do this as it gets really confusing, especially the first time your system refuses to behave normally ... use one configuration for the desk that can accomodate the entire show and keep it that way ...
 
edit #2:
another gig the guitarist couldn't make it ... so we unarchived his track from the rehearsals, put a life-size cardboard figure with an inflatable guitar on stage ... and voila, no cancelling the show ...

I am confused as to what the problem is here. I have been using the playlist feature for multi track audio backing tracks (between 8 and 24 tracks plus click to in ear monitors) with eq and fx on several of those tracks,  returned to separate tracks on a digital mixer (previously via firewire to a Yamaha 01x, now usb to a Behringer x32) plus midi for external device control and scene change for the past 6 years. I now also run DMXIS on the same computer and internally trigger it using loopbe midi to control a 20 fixture light show. I use an I7 laptop that is not particularly highly speced with an external USB hard drive for audio - and it works perfectly. I can change songs on the fly without issue, have the playlist continue to the next song, wait for keystroke etc without any unexpected behaviors.
 
What do you mean by changes your mix Georgerizzi? The crucial thing with midi is to ensure that your midi output device order stays the same.
 
As far as songs opening on screen as they have previously, you simply need to go through your songs and set the screen how you want it to look (adjusting the size of the arrange arrangement window, and whether you want lyrics view etc), LOCK THE SCREENSET, then save the  song. Next time you open it (whether manually or as part of a playlist) it will look exactly the same. 
 
Playlist is a great feature - hands down the best way to control your live playback. And it works:)
 
 

Thanks for the input. The project is still shrunk but thanks to yr tip re screensets the dock no long appears and covers everything. The way the project resizes allows me to see the notes section on the playlist so that should reduce the need to see the waveform right away. Much obliged.

Happy to help mate:) Well worth sticking with the playlist.