The lesson to release blockers with walkers etc is subject of a level in the next rank, which your format excludes. That's why it's called "Basic Training".
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The things missing you mentioned at the end are all addressed in the following ranks, especially the experimenting/creative learning part.
I figured it might be the case that the next few ranks introduce more creative learning; that's great, for sure.
I'd still assert that one or two levels in these early ranks being more along the lines of "any way you want" would not go amiss, to help propel the player through these more instructive levels.
The hotkeys displayed in your test are taken directly from your setting, so if there is a "None" then it's missing in your settings. It sadly cannot recognise all your special mouse buttons though, so that's why it's not 100% working for you here.
My mouse side buttons are configured to key presses (via X-Mouse Control), so not sure why these don't show up... maybe it's because they're Numpad keys?
I highly disagree though with pointing beginners to the original games or packs with just loads of skills, as these doesn't really teach anything in my opinion and the player will be WAY worse off.
I disagree; everybody has different learning styles. You're clearly more suited to being given specific instructions and having a specific path to follow. I get frustrated with this, since I prefer to learn in a more exploratory, experimental way.
My first driving instructor insisted on explaining everything in detail, and spent the entire first lesson on seat belt, mirror checks and theory of clutch control; the car never moved. Needless to say, that was the only lesson they ever gave me. My next driving instructor took me to an empty parking lot and had me driving around corners
and reversing by the end of the lesson. And, they would only explain things to me in detail if I asked. That was the instructor I stuck with (and, incidentally, I passed both theory and practical tests first time).
Players who play this pack won't get stuck on "Postcard from Lemmingland" and "No Added colors or Lemmings"! I teach those behaviors!
I didn't get stuck on either of these levels, wierdly; I completed both without hints. Strangely, the ones that stumped me the first time I played them were those featuring splat drops with not enough Floaters (
Pillars Of Hercules,
Steel Works) and those requiring reverse-facing skills to prepare the path (
The Crankshaft,
Mary Poppins' Land). To this day, I've no idea how I was able to figure out the various tricks required to complete
No Added Colours whilst the arguably more obvious reverse-Miner in
The Crankshaft had me reaching for the manual...!
Thank you very much for the feedback though and I noted some things down for the next patch! 
You're very welcome, and it must be said that
you've done a more than admirable job of the Introduction Pack, it's a pack that NeoLemmix definitely needs. I've suggested in its own topic that it get bundled with NL along with Redux.
I agree, let's split this discussion off into a separate topic, if possible. 
No need to do this, mods. Learning styles is relevant to first rank levels, since many of these are aimed at teaching the player.
I'm with Proxima on this one: theory-driven learning can be frustrating for some people, and the
Introduction Pack is a bit on the text-heavy side; I forget information presented in the preview screens on at least 3 occasions during the LP (one such instance leaving me unsure as to what the point of the level was).
However,
I can recognise the importance of theory, and it absolutely should be learned, but
not necessarily in the first instance. I'm more of a
practice-first, theory-second learner. I like to discover something on my own, then find out exactly why it worked. Having something explained to me before I've seen it in effect is very unlikely to gel in my mind, because there is nothing for it to gel
with at that point, it's just abstract.
Ultimately, different people learn in different ways. The OGs cater more to my own learning style, but I can certainly see why the
Introduction Pack caters better to more theoretical learning styles. I work in education (or, at least, I did) so I'm well aware of the need to differentiate learning based on these sorts of things.
