Check elevation datum point

Is there a way to check the elevation of componenets? I’m using the free online version on Windows 10.
I rotated several components and some were all 1/4" lower.

I’m going to set snap and angle snap to zero…see if that eliminates my crooked barn.

Can someone expound on “unlocked plane”, please. I’m not finding anything on the subject in the online tutorial. Manipulating the snap setting didn’t help.

I’ve finding changes each time I load a drawing from Trimble Connect. Must be climate change…