I still let my girls out when it is dry from above, the grass here is always wet atm. The goats do not eat much, except the two on the diet, who graze as soon as they are put out. The rest just messes about just outside the door... so will stop soon and keep inside until the spring...
Egglady - it would be good for them to have daylight, and even better for you milking and feeding etc in the Scottish winter if there was electric light... I couldn't do mine without light in the winter. If you have light, water (not frozen) and horses for company I am sure they would love to live in a horsebox during the winter, and it may be a lot easier for you to give them hay, water etc etc...