Hey Takiro, I've asked TPTB regarding the maps and basically this is what I got:
1) the maps are political maps and not jump maps, so
(a) just because the system does not appear does not mean it's undiscovered or abandoned at that particular time (and there are no official rulings on what systems exist when except for a few that have been posted on "ask the writers", but they don't consistently answer all questions). The best bet here is if there are any in-text doc that says when a system was discovered/colonized/abandoned/destroyed/etc
(b) there are some systems (Mica, Niops, etc) that show more than one planet on maps but are actually just one system. What I did here was get the average X and Y coordinates and the result is what I used for the system coordinate (crude but it's the only process we have in the absence of official coordinates)
2) allegedly there are official coordinates but it would appear they would never see the light of day, so there might as well not be any. Since the declaration that the housebook coordinates are no longer canon, the coordinates released by Syntax and myself are to date the only "complete" attempt to map each system's position. I say "complete" because for every new map released that contains more comprehensive information it's possible that older released coordinates be rendered obsolete. This is because of:
(a) the inaccuracy in the 12-LY ruler as X-scale
(b) the absence of a true Y-scale reference
(c) limited number of reference points when plotting far systems (JarnFolk, Pentagon, etc) against the inner sphere. ISP3 is the first map that I have that allowed me to position these systems using Terra as my anchor point. If we take the Y-scale of the ISP3 maps as correct, then it turns out that the KCluster should be 16.5LY farther, the Pentagon 1LY to the Left and 14-15LY higher up, Imperio worlds 6LY to the Left and 10LY higher, Hanseatic League systems 7LY more to the left and 7.5LY higher, JarnFolk 5.3LY to the right and 5.2LY higher, etc...
3) even then, we cannot fully rely on the coordinates and scales because according to Oystein the maps are warped (non-uniformly scaled) when they try to fit them on the page during layout. I don't know how true this is but since we have no access to the raw maps/coordinates, we have to accept them at face value.
It's actually like working on quantum mechanics. The coordinates are accurate up to a certain value within the limits of the TPTB Uncertainty Principle. But that's not stopping me from making coordinates for those who wanna use em. If TPTB want me to stop then they'd better come up with a more accurate one than what Syntax and I made.