Pro channel Comp For Finger Style Blues

I don't use Pro Channel much, but I can give you some starting points.
 
First, it depends a lot on your playing style and technique, but with that caveat...
 
most folks use a compressor to try to even out widely varying dynamics, so if you find that your fingerstyle performance tends to accentuate one or two strings you can use the following as a starting point:
1) attack - probably slower than you expect, you want some of the attack transients to come through
2) release - probably faster than you might expect, you want the compressor to be able to react to the next transient
3) ratio - I tend to use a low ratio because I don't want a lot of compression, but if your playing is somewhat erratic (in terms of dynamcis) you may need to use a higher ratio to even things out
4) threshold - again I tend to have the threshold set close to max to minimize the compressor action. Same idea as ratio applies here.
 
All these things will interact, so you need to find a method for tweaking that works for you. Here's what I will usually do:
Set the attack at it's slowest, the release at it's fastest, the ratio at it's highest, and the threshold to something silly low so that the compressor is almost always engaged.
 
First I tweak the threshold till I am hearing the compressor act only on the most obnoxious transients. Once I find that spot I lower is just a little bit more to account for the other changes I am about to make (maybe 2-3 dB)
 
Next I tweak the attack to allow some of the transients to get through, and then I back off on the release time so that the compressor action is still audible, and in fact it'll probably pump a bit at this point.
 
At this point the compressor action will still be audible, maybe even very audible, so I reduce the ratio, usually to the lowest setting, but maybe a little higher.
 
At this point I should have evened out the attacks, and created a 'graceful' release so that things are smoother. There may still be problematic peaks getting through. If there are I will add a limiter or second instance of a compressor with a really fast attack time, and a release time at least 10X the attack time. Ratio will be set to the highest setting (infinite if available) and ratio will be set 2-3 dB below clipping. You may have to tweak attack and release times to make this inaudible.
 
These guidelines ought to apply to almost any compressor with attack/release/ratio/threshold style controls. If you are using an 1176 type compressor you don't have the threshold so you have to play with input and output levels to adjust the threshold, but it is the same idea.
 
Have fun!