Does it keep the sb mode after shutdown or do you need to pgusinit /sb every time?
I admit it was a while since I used the picogus and I think it was before the last pgusinit update. I believe it used to work even without the environment variable but I could also be imagining things :) I might have had it set.
Perhaps I should look at getting rid of the check for it in the Atari version if it's causing a hassle.
You can add the environment variable though, using a program of your choice that lets you set them.
I found a few and there is an open source one included in the raven package: tools/setenv.prg
There is also tools/autoexec.prg that'll let you run programs with commandline options which can be quite handy.

