omega, to save simply go out of a town, and click the save button you'll see at the bottom left.
i don't know why you are unable to save in a town though :/
the way i beat not so vast forest is (and i had 4 points at the time) i bought all the extra live things (and scouts, not that it matters just needed the investment) and then got all poison warriors with specialization consecrate. fairly simple.
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