Your dealer is not a very good one. Sorry you had to buy a tractor to find that out. /w3tcompact/icons/frown.gif
Try this:
It will be easier if you can hook something up to the PTO that you can see moving such as a mower, but not absolutely necessary.
Engage the pto lever with the clutch pushed all the way in.
Put the tractor in the lowest gear.
Have someone stand way behind you and tell you as you let out the clutch when the pto moves. The pto shaft should spin before the tractor starts to move. Try to gage how much further your foot has to move before the tractor starts to move. It will probably be about an inch.
Stop the tractor and put the gearshift in neutral, but leave the pto engaged. The pto shaft should be spinning with the clutch out. Push the clutch in to about the same position where the tractor started to move before. Wait at least 15 seconds and see if the gears grind. If they do, push the clutch in a little further and wait 15 seconds and try again. You should be able to engage the gearbox with the pto shaft still spinning if the clutch is working properly.
Caution: The PTO shaft is very dangerous. It will tear off body parts in less than one second if you get shoelaces or other clothing tangled up in it. You should normally turn the pto lever OFF before dismounting the tractor and not let anyone within 10 feet of the shaft while engaged.
A note: New clutches sometimes don't release very well. I assume your gearbox is not synchronized in any gears or you wouldn't be hearing the gears grinding. If it is synchronized, then you will get much better at doing this after you have 100 hours on your tractor. Both clutches releasing at the same time will not have much effect on anything and it is human nature to push the clutch all the way in. Just use it that way for a while until you get the feel of it.
The purpose of the 2 way clutch is to allow you to engage the mower and let it come up to speed before you start moving forward. I am sure that if you think about it that way, it will perform as you expect. Sometimes the hydraulic pump will not operate until the first clutch is engaged. This is noticable when using a loader or other hydraulic device while starting or stopping the tractor.