Danger danger!!
Here we go again with the "electronic trip" providers giving really bad directions. I have met a few very confused people in the bush that were given instructions that put them onto one of the many logging roads of Vancouver Island.
The road that goes around Comox Lake is an industrial logging road! Yes, it's possible, but do you want to shake your unit apart? I doubt it.
The normal route is get to the Island either via Victoria or Nanaimo and head north. You can do the tourist route by deeking off at Parksville and stopping at a great country market in Coombs or stay on the 4 lane and turn off at the quaint village of Qualicum and head west.
Less than an hour from Parksville to Port Alberni and about two hours to Tofino from there. Sproat lake has a nice provincial campground and is a great swimming lake if you need a stop along the way.
Port Alberni has nice quay at the waterfront and bakery that does home made donuts!