Hi,
when I tried some bad-and-good things on ZDBSP. In all these cases, the input WAD is filled with one Hexen-style map level (MAP01).
1. removing the BLOCKMAP entry in the input, creates the BLOCKMAPs in the output, as well as a duplicate BEHAVIOR entry.
2. removing one of the vital node parts (SEGS,SSECTORS,NODES) -- I tried with NODES -- zdbsp skips the map, even though NODES is not needed as input, as it is being rebuilt.
That's all so far. And a suggestion: add a REJECT builder to it.