Filler blocks in Blueprint become offset from the regular blocks so that your air-spaces do not align with your base blocks. Note the torch is next to the entrance hole. But when spawned, it is way far away to the left (hole is on the right). As you see in the pictures, the filler blocks end up offset from the other blocks. Compare creative mode positions vs spawned-in by playfield. Notice that the HUD marker is way off-center. The base was created by adding a core, and then using the build menu's "select" and "fill" functions. I suspect the marker stays aligned to wherever the core starts out. When generated the fillers are adjusted to center the marker on the base, but it does not adjust the other blocks. (or vice versa.) This can be fixed manually by copy/paste with the entire blueprint... but you have to count out the number of blocks needed to move. This happened to me with two different "cave" builds.
You can reset the pivot point of the blueprint with the following command: prefabinfo 'Name of Blueprint' -clearpivot This command is basically required to run whenever you change the bounding box size of the blueprint otherwise it will cause the issues you see.
