I'm setting up my various control surfaces and have been diving into ACT.  It seems to do what it says on the tin, but I can only map 16 controllers at a time to VSTs in the "ACT MIDI Controller" tool.  Is this a limitation of LE?  What if I have 50 knobs, are 34 of them just for show?  So far I can't find any info that indicates whether other Sonar versions have richer controller schemes available.
 
 

You have more than 16 controllers you want to use at a time?

OK, slight correction.  By "controllers" I guess I meant "parameters".  I have three "controllers" totaling 40 knobs/sliders.  I have mapped them in MIDI-OX to one MIDI loopback device which Sonar sees.  This all works fine.
 
But anyway, only 16 parameters can be assigned to plugins at a time.  There are another 16 that are reserved for controlling host parameters.  The VST I'm using is an FM synth that has at least 100 parameters. 
 
One solution I tried was to create 2 ACT controller instances, but then it turns out that only one of them can control a given VST at a time so that's no help.
 
This is the ACT UI I'm talking about:

 
 

Gave up on Sonar mapping.  Vsthost does what I need:

 
It can be used as a vst itself, so I can continue working in Sonar as before.