I was the first to mention Lake Mountain, here is a little clarification.
The new descent is in three parts. First part is a reworking of the old descent from Sherlock Lookout to Snowy Hill carpark. You then climb to Snowy Hill which is followed by an awesome new descent to Arnold Gap (but pretty raw, not nearly as groomed as the BMX track on steroids that is the Epic Descent. Needs a a season or 2 of riding to really bed-in properly). The trail from this point is pretty raw but definitely ridable, climb Mt Arnold then descend to the Entrance Station. Its then an easy spin on the bitumen back to the top. Or you skip the last part and spin back up on the road from Arnold Gap and have a second crack at the first two sections of the descent. Note that they are solid climbs between each of the three descent sections.
A good ride plan would be park at Arnold Gap or the Entrance Station, spin up the road to Snowy Hill carpark, turn left onto main loop, ride full loop then climb Snowy Hill and descend to Arnold Gap. Depending where you parked and how the legs are feeling, you could do repeats of just the Arnolds Gap descent, the full descent or what ever you feel like.
Being very soon after the winter season I would expect a lot of branches, bark etc on the trail so take care.
Hope that helps!
P.S. I believe this descent was done by Dirt Art - the guys from Tassie.
P.P.S. Lake Mtn is very close to Buxton. Stay the night in Marysville and do one each day. Buxton is less technical, flowy, bags of fun. Lake Mtn is rocky in parts, more technical, has a real "alpine trails" feel, much more climbing than Buxton.