holding the lever up to insure engaging sounds like adjustment of the rod from the box to the trans - the "clamps" on the levers at the box are adjustable for the length of the rods, one of them isn't moving far enough .... for the fork out of position, you need to have a helper work the lever inside up and down gently while you get the fork back where it belongs -
see here, and insure that the spring in there is not broken
Bill