This skill is currently misclassified, its a Commander level Engineering BOff Space skill, but when attempting to replace it with another space skill, it returns "replaces unknown node", and when mousing over Aceton Field II on the BOff skill store, when I mouse over an engineer, it says it replaces the Engineers Commander level ground skill.
Thusly I can't replace the 4th tier power for my Commander Engineer, and we're running the Commander engineering station with only 3 abilities.
I've heard that this can be "fixed" by replacing the same rank ground ability with something else, since it's misclassified as a ground skill.
Tried that, I swapped Quantum Mortar Fabrication for Medical Station Fabrication, and I still cannot swap Aceton Field II for Eject Warp Plasma II...which is the only other Commander level Eng BOff space power, it continues to give me skill replaces unknown node.
I am also having this issue, My main engineer even learned Aceton III from one of my random requited officers from leveling... This removed her 4th teir ground box entierly, then added a 2nd 4th teir space box. So I had the skill Aceton II and III listed in my space abilties. Howeveer when using my cruiser the skill does not display at all and is not usable.
I am also unable to train it out as I am getting unknown node. When I had my engineer relearn support drone it removed aceton III box entierly and gave me my 4th teir skill box back for ground.