From your heading it's a conservation type and not standard kind?
I've fitted quite a number of both types over the years and they aren't too difficult as long as you take care with the flashing and weatherproofing detail. I would think a felted shed roof wouldn't be a problem though I would renew the felt if possible at time of fitting. I also think you need the one made for slate roof not tiled as the flashings are different and you might need to be generous with flashband and silicone.
Why do you need a conservation type on a shed btw? Or is it that you have one spare?