This is a list of new parallels that I come across from time to time.
AN 5.255=pc7*, pc44*, pc45*, pc46* (This is an interesting link between sutta and vinaya. The wording makes it clear that the sutta follows the Vinaya in this case. But the sequence is different to the current Pali text)
At AN 6.63 we have a cross reference to Kv 2.4. This is incorrect, it should be Kv 8.4#33. This is, I would guess, a systematic error that needs looking at. Also, in the Kv the SC paragraph numbers are not per text but per chapter. Again, this needs looking into. We should be consistent.
Cross references are in the Pali texts, not in the CSV files. This is one of the things we need to do for our JSON project, extract such references so that all parallels, including cross-references, are in one unified format.
From what I have seen of those that I extracted from the DHP: most of them are wrong! You can see in this specific example that the reference is to Kv 2.4 Aṭṭhamavagga/ Kāmakathā - the second part of the reference is correct but the number is wrong. This is something I have seen in the DHP very often too. Like you said, this is a systematic error.
I will write a little python program to extract them all into one file, but still they would need to be gone over by hand (maybe ask for a volunteer?) and then added to the JSON database I am working on.
I C. I will make this an issue on Github and can renumber them using the python tool for that. But this will also have an effect on all parallels and cross references referring to those.
(PS. Not sure if this issue should be here - which is the post for adding new parallels)
I think the thing to do will be to discuss it with @Blake first, as he prepared these texts and will be more likely to anticipate such systematic errors. I have got the impression, and I may well be wrong, that the situation is different in different texts. We might find the four nikayas are okay, but other texts more problematic. It might be useful to check some sample parallels across different texts to see if this is the case.
But anyway, let’s see about having a chat with Blake sometime soon and we can discuss this.