I tried a map of yours with pak.ngb in Extended a couple of months ago, and then it worked.
Fam, I think the first thing to check if it does not work:
Open config\simuconf.tab and change the value singleuser_install= to the opposite number of what it is (if it's a zero now, change it to one. Or if it's a one now, change it to zero). Whenever the game doesn't load properly for me, it's because that value has been changed (I use the one value, but James has the zero value on github), which it occasionally do when updating.
But I might be wrong and the pakset really isn't working in extended, I will test when I get home in a couple of days.