Possible backroute to Slipping Again that uses 0/1 climbers (1 left over) and 1/2 walkers (1 left over), but at least all 5/5 builders and 2/2 diggers. It feels sensible, but the leftover skills raise an eyebrow.
The main trick is digging close to the steel, to make a narrow digger hole that's quicker to plug shut by building inside.
-- Simon
since Nortaneous isn't around all I can say is
the main tricks of the level(s) is the building inside a digger hole. If that is preserved it's okay by me.
Initially I think what I was going for was something along the lines of ccx's solution to the original level which looked something like this;
builder bricks: -
terrain: =
-
-
-
-
-
-
==== =========
==== ========
==== --========
==== ========
==== =========
so the lix will fall into the digger pit then turn around on a tiny builder ledge inside. But I don't remember if this was able to actually be preserved in the final level as this went through many revisions and backroute fixing.
Honestly I don't remember why all the steel was even put there. I don't think there was originally any steel at all. Obviously to fix some kind of backroutes, but I could be wrong.