I think, part of the problem (might even be the solution) is the coordinates format!
I took 2 older Grind profiles - all of them contained basically valid coordinates (verified the position via HB Dev Tools) BUT they did not work, because the coordinates format looked like: xxxx.XXXX, xxxx.XXXX, xxxx.XXXXX. As soon as I changed the coordinates format within the profiles to coordinates with only 2 digits (for example: X="-2225.63" Y="8850.12" Z="5.31") at the end - everything worked just fine.
Questbuddy locking up on me makes total sense too, if the reason IS the coordinates format... see:
[09:10:38.717 D] Could not generate path from {1770.091, 6538.903, 65.93395} to {-232.92, 1028.272, 54.3632} on map Expansion01 (time used: 0 milliseconds) @ FindStartPoly
[09:10:38.733 N] Moving to Type: QuestPickUp
[09:10:38.733 D] Could not generate path from {1770.091, 6538.903, 65.93395} to {-232.92, 1028.272, 54.3632} on map Expansion01 (time used: 0 milliseconds) @ FindStartPoly
[09:10:38.749 N] Moving to Type: QuestPickUp