From your description it sound like Sonar believes the MIDI is coming from the MV instead of the Fantom, right? How about vice versa? Can we review the cable connections? Four cables, no cross connections between the two external units, right? Do you know if Sonar treats your two Tascam MIDI ports in the order you expect?
 
As far as WDM vs ASIO is concerned, that is mainly an audio issue. The MIDI driver configuration should be handled separately by Windows.

After trying all these different configurations I'm realizing the may be that the 1884 and/or Sonar are not letting the 2 ports midi in/out port 1 & in/out port 2 communicate. There has to be a way for that to work. For instance If I ran midi in/out from the Fantom to the MV8800 it would work flawlessly (it has). But what's the point of having 4 in/out ports  if they will not interact? I can't run the MV & Fantom exclusively because I would not be able to use the software synths as the MV only has 1 midi in 2 midi outs and the Fantom has 1 of each and a thru. I'm stuck. 

BTW... @Mystic, 
I was trying to get the Fantom X drivers to reinstall but since I moved to Windows 8 alot of programs & drivers will not function correctly. You'd be amazed at what I had to go thru to get my Firewire interfaces to function on this new Windows 8 system.


@Bvideo, 
Thanks for responding. Yes Sonar is seeing my ports as it should as I said depending on the routing I can get the soft synths to function in the Fantom as I just can not get the Fantom to trigger the synth sounds & MV88 together and the MV88's sequencer.

Five0SixBand
How did you do that screen shot? 

On windows, Alt-Print Screen will capture the view in the active window. With a menu highlighted it will normally capture the menu as well.
 
Posting it was another matter in that it requires a url. A couple folks had some suggestions on this thread http://forum.cakewalk.com/FindPost/2915605
 
Michael

Thanks mettelus!

Can't wait to try it.

If you have a bunch of 'real" midi gear... take a look at the MOTU micro express, and Midi Express XT.
 
These allow for software programmable midi interconnect between devices and from devices to the PC...the Micro (4-in, 6-out) can be had for ~$50 used on Ebay.
 
note: see by your sig you have moti 828..tried that midi port for one of the units?

Yea, looks like I will have to go that route. I was trying to avoid adding more gear to my set up/ Just creates more confusion & more to learn. I was looking for a software that does the same thing but no such luck...

Finally got my midi express XT. Now to find the software,  learn it & see how it improves my work flow then decide if I wanna upgrade to X3.

has OP found a solution to this problem?

I have the 1884 and can try to help.