Okay, thanks for the feedback. i'll give it a second thought about the solo function on the dNa-Stereo Equaliser.
The reason why it was not included on purpose: in MS when you "shape" the channels using this equaliser the levels can change a lot, because it are rather wide equalisers; a coloring-box...therefor: it's best that you make the the final balance between M and S with the gain/levels after equalising, because it also controls the width of the mix. So the level of M or S can be turned down as long as you are equalising, and therefor a solo-button wasn't an absolute must...Then secondly the choice was esthetically and save dsp by not including solo buttons. But as said...i'll give it a second thought.
On the dNa-MasterCOMP and the filters: No, the filters are NOT working on the actual signal/mix itself. The SC-Tone filters are used for shaping the sidechain, and thus control HOW the compressor reacts to the mix-signal. For example: if you have a mix with a lot of low frequency energy (for example dance/electronic music) you can use the sidechain for shaping so the compressor doesn't go pumping "on the beat"; everytime a bassdrum hits the compressor reacts to much by compressing the mix. Also a "good" mix has a frequency distribution sort of like a pink noise curve. So a compressor works different on higher frequency energy/bands. The medium and SMACK filters shape the sidechain by attenuating lower frequencies and lifting higher frequencies and thus making respons more lineair on the frequency bands. Experiment with the settings by ear, a very nice default starting point i think is the vintage or medium setting.
And don't worry: It can take years to really know what your doing and can achieve with compressing, and use it to make the most out of it; also because there are different types. The dNa-MasterCOMP may look simple...but that can be deceiving. It actually is a complex compressor combining a lot of different analog techniques in one processor.
Soundwise and learningwise: you may also be stubborn....use ears: if it sounds good....tape it. If it sounds fatiguing you are probably overdoing it, so less treshold. Try reading some articles on compression because it can be one of your most powerfull tools for creating a phat and punchy sound, or give mixes some "glue".
The link-filters: check for some info on the website:
http://dnamusic.nl/dNa.Scope/index.php/dna-mastercomp
A typical limiter is usually use just on peaks so starting point in settings:
SC Style: Modern FF ; peak
SC Tone: Vintage or medium
Link filter: High pass, with 0-50 blend for limiting peaks on the L/R channel seperatly
Others: short attack, fast release, high ratio
There are presets for limiting, and of course you can use limiting for different purposes...because you can use it for more than just controlling peaks/transients

Actually....you may also just enable the analog feature, which can also "limit" fast peaks.
Hope this makes some things clearer.
Regards, Ray