All that room to hang and he wants to climb the roof! Grr!
I remember reading somewhere that it's normal for them to climb on the screens for the first day or so because they're figuring out their habitat. If it goes on for a long time, then that's a sign their enclosure is not comfortable
My vote is no, not weird for a baby. Both my baby veileds did this for a bit while babies. They would especially like to hang upside near the basking light (which is raised a few inches). They did all sorts of things that made a new mom paranoid, but grew out of (most of) them pretty quickly.
No. My Cham used to do it all the time. He used to be all over the top at the UVB lights. Now that he’s old and lazy now he’s stopped.