No, don't turn pregnant ewes unless you absolutely have to.
They get a bit limpy as they get heavier. Human ladies who've been pregnant themselves say it just feels a bit like that in the later stages
So long as she's coming for food ok, I'd leave her be, and give feet a good checkover after she's lambed.
If you think they're spreading infection to each other, move the feeding area around; if that's not possible, spread lime on the ground where they walk over each other's footprints. That'll kill most of the infective agents.
Sounds like the lick would do no harm - except that it creates somewhere for them to congregate and spread any infection to each other...
So if you can't move it about regularly I'm not sure I'd think it a good idea...