Two other ideas that came to me spontaneously:
1. the zoom and motion function we have with the mouse is a fantastic idea by the way, if you want you could create an extra attentional component whereby instead of an extra rotation function you could just have the motion function on automatic while playing so that its training our ability to stay focused on the block as its moving around from trial to trial within that grid space.
2. a fluid reasoning component / cognitive interference on the n-function: if you wanted you could implement the idea of the user working out the pattern of the presentation of the recognition function based either on a rule they have to workout prior to the presentation of the stimuli or after / based on the presentation of the stimuli.
I could give you a few examples if you like.
So in the case of the former, as I've privately already referenced the implementation of syllogisms something like this could be actioned in between the presentation of stimuli or what would be even simpler for people, basic arithmetic.
In the case of the latter, during each session not trial (as opposed to the former) as I don't have an example to follow for that right in this particular moment, there could be an underlying rule we need to workout that the pattern of CORRECT RECOGNITION OF MATCHES follows. For example, there may be the hidden rule of how the simultaneous presentation of any set of stimuli i.e. say the letter F, bottom area of the BLOCK (not the grid) corresponds to a match for the COLOUR if there is that PRECISE COLOUR MATCH if and only if there is also a SPATIAL match. This is the application of both the SPECIFIC (i.e. using the colour F and bottom area of the BLOCK) and the GENERAL in an "if and only if" (alternate relational reasoning component / relationship to syllogisms) and the GENERAL (spatial match), for beginners which I certainly would be in the bracket of I'd start with the GENERAL only, where recognition matches are only recognition matches "if and only if" there is a certain simultaneous combination of other GENERAL matches or non-matches depending on what the actual underlying rule is.
I'm barely making it through n2 at the moment so I don't really see the point at the moment but when I can get to 3 and beyond it makes more and more sense to apply extra but HIGH QUALITY reasoning components (the definition of which we could get into at a later date).
I can see my attention already improving and I'm only in my second day nearly third hour (2 minutes and 25 seconds away on the clock however in the sum of quality training I'm probably another 20 minutes or so away) of training thank you Fredo!
So utterly, utterly grateful! :-D