It's quite easy to skip the horrid tarmac road approach.
On the main road leaving Llanberis, just after you pass the final entrance into the Royal Victoria Hotel,(the one nearest to the chapel on your way towards Pen Y Pass on your left hand side) you will see opposite on the other side of the road, a small entrance with large stones, and a sign please asking people not to park there.
Just by the large gate on your immediate right, you will see a style leading into the forest.
Follow this snaking twisty path for around half a mile, on very easy ground, and you will eventually arrive right behind the cafe, at the top of that awful tarmac road.
Its an alternative route that many visitors trying to climb Snowdon, simply do not know about, and it saves around ten minutes of walking time, and cuts out all that nasty bit of tarmac as far as the cafe.
Sorry to hear you had to turn back at Clogwyn Station, but on my way home Saturday evening, looking towards Snowdon from Roman Bridge, the whole mountain looked ever so intimidating.
At least you know what to expect, on your return journey next year, and now know how to avoid the tarmac nightmare.