I've skimmed through the other threads, but don't see this specific problem, so forgive me if I've just missed it.
While trying to get a Proposed Conditions surface out of one file and into the Existing Conditions file (in an effort to merge the two), I attempted the WBLOCK insertion technique. When the WBLOCK is first inserted, it looks perfectly placed. After exploding it (so that it appears as a viable surface in Toolspace), I get error icons... ...then after rebuilding it... ...the surface gets thrown horizontally into space (not very far away, but offset nonetheless).
The manual describes a "double jump" phenomenon, which may be happening here, but the manual's solution is to maintain the insertion point at 0,0,0 - which is exactly what I've been doing. I've tried changing coordinate systems, binding an xref, data shortcuts... ...to no avail.
I've run out of options and since I'm just learning Civil 3D, it's probably something simple. I appreciate any guidance.