You've opened a tin of worms here Mike. Keeping worms is a good topic, and I'll be interested to see the replies, too.
Worms don't like big temperature changes. Best keep them cool eg on the garage floor. They're fridged in the shop, I know, and I've tried keeping mine like that, but I think it can get too cold.
Check the medium they're in isn't drying out.
Feeding them, the best thing I've tried has been chicken feed! You can get bags of something called Layer's Mash - looks a bit like dried breadcrumb - and I damp this a bit and put it on top of the peat they're in. It's very satisfying when you check and find it's been eaten. But if you put too much in, it quickly goes mouldy. Last hot tip I read involved mixing a bit of Smash with a used teabag. Gourmet, stuff, Mike, so get your apron on.
For all the tips out there, I have to say I've found keeping the worms going for more than a couple of weeks a bit hit and miss. Sometimes it goes well, and I've had worm happy enough to not only stay alive but reproduce. Other times, it ends badly.
I've tried keeping them on a larger scale, with large boxes, a good layer of peat over dead leaves, a feeding regime etc...... but never really cracked it.
Just now, I'm puzzling how best to keep lobs alive and in good nick with a mix of moss and shredded cardboard.
At the risk of seeming weird, I'll admit that I feel a bit more responsible for the welfare of worms than I do for eg maggots. I have no qualms about chucking out any maggots that are past their best, but I I hate "losing" worms. Maybe it's because they seem more sophisticated creatures??