When I was running a TA wing, I would put it in the up position as soon as I could and probably 99% of my drives were that way. I just preferred that look. I ran it that way for quite awhile before going back to an oem wing. Never had an issue or ran into any dash errors/CELs.

It’s bad, yes. The high force springs in each ram keep a very high pressure on the entire hydraulic system. With the wing down, the force exerted is greatly reduced (yet still present) which continues to force the fluid out at any breach. More info HERE.