After a few tries, made it down to the 5th floor. I do wish it was a bit less totally random, and there was a floor counter, but was still fun. Plus, you have great cover art.
One way to free up some bytes would be by not storing the central dot in the lists of your lists of die pips, and just drawing that whenever there's an odd number:
function u(f,n,e)
r(f,n,f+8,n+8,8)
if (e%2==1) pset(f+4,n+4,7)
local d={
[0]={},
{2,2,6,6},
{2,2,2,6,6,2,6,6},
{2,2,2,4,2,6,6,2,6,4,6,6}
}
for i=1,#d[e\2],2 do
pset(f+d[e\2][i],n+d[e\2][i+1],7)
end
end
Takes that drawing function down from 252 characters to 189. Could shave off a few more by making `d` a global.