AUS-ACT M23:
- relocate LimeKilnRd to halfway between RIROs
You mean LILOs! 
Er... yes, that would be how that works wouldn't it.
Funny thing about countries that drive on the opposite side of the road from what I'm used to - my brain tends to want to adapt to this by simply mirroring the definitions of left and right, since this is easier than having to re-conceptualize the significance of every instance of either word.
This works great in my head, but it makes communicating concepts of relative direction to others challenging.
Anyway, moving on...
N end of Sydney section
As I've had time to think about it a little more I think the endpoint is correct as mapped, because it makes M1 continuous with A1, and that's how routes in Australia seem to work - the same number will run for an entire corridor but change classification where warranted.
The location of the M1/M2 junction probably needs to move east to where the carriageways join though.
And here's batch 2 of comments.
AUS-NSW M1Kem:If kept in ausm the following applies:
- NSW12/14 -> T12/14
- MacValWay_N -> T12_S
- MacValWay_S -> MacVlyWay
- NSW10 -> T10
AUS-NSW M1Uru:- despite being motorway grade this is all signed as A1. Join with A1Eun and A1Cof
AUS-NSW M1Wol:- combine NorAve and UniAve (one point per interchnge)
- 5IslRd -> FiveIslRd
AUS-NSW M2:- check east end (see also comment on M1Syd)
- A2/A40 -> A2/40
AUS-NSW M4:- combine ConRd and A4/44 (one point per interchange)
AUS-NSW M5:- M7/M31 -> M7/31
AUS-NSW M7:- M5/M31 -> M5/31
AUS-NSW M15:- OK
AUS-NSW M31:- Some drama going on with exit numbering on this road. It appears exit numbers 1-12 were added to the route in ~2016, as a sort of pilot project perhaps. Then, in April 2018 the exit numbers south of exit 6 were removed. This is generally corroborated by looking at GMSV imagery from different dates, and is also noted in this thread on the Aussie Highways Newsgroup:
https://groups.google.com/forum/#!topic/aussie-highways/2y5W7_vnKHUSo in terms of point labeling that gives us:
- M5/M7 -> 1
- A28 -> 2
- CamRd_Cas -> 2A
- BroRd -> 3
- CamRd_Ing -> 4
- RabRd and CamRd_Woo -> 5 (numbered exit and one point per interchange)
- A9 -> 6
- 7 -> B88
- 8 -> AvonDamRd
- 9 -> T12_Yan
- 10 -> T12_Col
- 11 -> B73
- 12 -> OldHumeHwy_Wel
- OldHumeHwy -> OldHumeHwy_Ber
- add point for interchange at Sally's Corner Rd (south of A48)