Thank you everybody for your feedback!
Few time to answer in detail now, I’ll do it later, we are busy working on Mac version + update (free for all current customers), but in a few words:
@Omnibros_Productions:
Dynamic EQ is probably your best bet. […] apologies to OP. at least my post accredits […]
No worries, and yes what you typed is also useful! Always good to have two different tools available rather than one!
if nothing else, wanted to share my case study with you, since people
mastering tracks frequently need to abstract elements and re-composite
them again under varied condition. you touch on this under “mixing:
raise or lower volume of drums in a mix” […]
your tool could be huge in mastering, and mastering is not mentioned anywhere in the product description on your page.
Totally true, as you mentioned, it can be very useful in mastering. We should add a mention about this.
Currently, you can extract drums, and add this extra layer of drum on top of stereo mix (and balance it with a fader). Even if this “extracted drum” is not perfect, as you blend it with the original mix, very few artifacts will be there in this context.
In the forthcoming update, it will be even easier, because we’ll provide a full range of mix with a fader between 100% percussive and 100% harmonic. Ok you can already do it with the current version (by adding an extra track that you balance with the fader), but with the update, it will become even more handy.[quote=“Ag_U, post:9, topic:8702, full:true”]
I don’t exactly support anything created to rip out stuff from other people’s tracks, but I’m kinda interested in what Harkat said.
[/quote]
Well, it’s a tool that you can use for good things (mastering, drum learning purpose, or even sampling if you ask the original author and “clear” the sample before release of your song, like everyone does now) or bad things, so I wouldn’t say this tool was created to rip out stuff… 
I suppose the algorithm detects peaks and gates out the sound around
them. How does it work when the track is mastered to -7dB/RMS (which is
nothing uncommon these days) and the peak volume is steady 0dB?
As a general rule, don’t expect this tool to work on all songs. It’s like a surgeon tool that you use for specific purpose, e.g. “I want to isolate the drums from this song from 2’10” to 2’15" " etc.
But the song that I used as example on the website (Tame Impala song) is a 2015 song, mastered with a very high RMS if I remember well, and it worked quite well.
@everybody:
trial version
We haven’t considered up to now, because we really don’t like iLok / dongle solutions, this is really annoying for the user. A solution like “2 seconds of white noise” every 10 second wouldn’t be useful as well, because then it’s like making this plugin free and stopping our R&D for future products! Lastly, I have never seen a protection like “30 days trial version” that really works. Change the computer date or uninstall/reinstall it and you’ll have it forever!
DrumExtract could be a solution then (I’m not claiming it would turn your job from hours into a few seconds, but for sure it can help).