The file attached below includes a sketch that I think reveals a bug in the dimensions/constraints solver. No dimension is able to be modified without a solve failed error, however deleting any dimension allows the sketch to be dragged along the axis that the dimension was defining.
Seems to be fine now for me too. I can modify the dimensions after restarting Fusion 360. I even tried recreating the sketch in another file and I cannot recreate the problem. There was an update when I restarted, so maybe it just happened that the update fixed whatever issue caused my problem.
