If you know the checksum was zero before running the checksum loop, you can just do full $4000 DUP on first area (no need to split it), the result should be same?
(or you can clear it before checksumming with `ORG $14E : DW 0`)

And then you can probably create macro for $4000x bank checksum with arguments for entry address+slot+page and use it for all parts...

Etc... I'm generally not interested too much to include this directly into sjasmplus git (N-logo for sure *NOT*, the checksum macro... maybe, but it's trivial to write if you know the sjasmplus syntax).

So I guess it's enough to have this documented here on the forum, or maybe somebody will write some public blog about "how to use sjasmplus for GB development"... (somebody not connected to sjasmplus project in any way and published on unrelated web not connected to the sjasmplus).

Thank you very much NEO SPECTRUMAN for testing it and for the syntax research info - it was essential task to make this happen (I think any major issue would be already found by now, so I guess LR35902 feature is of decent quality). (of course if any bug is found, let me know, as always)

Have fun.