I am in the process of installing a new bathroom up stairs and
changing the position of the toilet at the same time. The new toilet
position is at 90 degrees to the old-I am doing this by moving a stud
wall and putting the toilet against the new wall. I have two points
with respect to the new waste pipe lay-out that I would like advice
on:

1) I have had to extend the waste pipe. The total length of the new
horizontal run of 110mm waste pipe is 1.5 m. There are 2 elbows in it.
Will this horizontal run cause any problems with the toilet emptying?

2) The vent stack is now in the horizontal run-300mm before the
vertical waste pipe drop (1.2m away from the toilet), so the waste
flow goes past the vent stack before descending the vertical stack
into the ground pipe work. Will this effect the function of the vent
pipe?

Additional information: The house has had 4 toilets, 2 upstairs and 2
down stairs, but I have removed 1 down stairs toilet and capped the
waste pipe. There is 1 vent stack in the house -it is upstairs. The
waste pipes are internal. The new toilet is a duel flush type.

Please advise if there are any concerns or conflicts with regulations.
Thank you.