MP3Tag = incompatible because it uses TXXX frames ?!?

[chrizoo]

First of all ... what do I have to do to add nested quotes here ? I click on "multiquotes" on and off, but that doesn't change anything. When I reply to a specific post, I can only quote the last post, not the quotes inside the last post ...

@dano

Multiple values should stay unless you edit them in the columns view or [...]

What's the problem with the columns view? And why is this different to editing the tags with alt+T ?

but although I have the most recent version (3.4.6) and it can read the tags saved by Picard, Tag&Rename converts them to 2.3 tags (no warnings, nothing in the options to change that). In MP3Tag, you can see with %_tag_read%[ (%_tag%)] that they were 2.4 before and 2.3 after.

Can you confirm this ?

@dano

If you add the tags with Picard, Mp3tag should keep all info as it was.

In order to know, if all info is kept as it was, one would need to know four things:
(A) The scope of the editing, i.e. if I change one field of the id3v2.4 tag, is MP3Tag only saving this one field or the whole tag ?
(B) If the whole tag is saved instead of just this one field, are the other tags left untouched, i.e. rewritten 1:1 ? Or does MP3Tag interpret the tags, relate them to its own TagMapping and then rewrite them?
(C ) Is it save to assume that tags can never get "lost" because MP3Tag either supports it natively, i.e. uses the frame as defined by id3.org, or if it comes across a TXXX field, it is supported as a custom frame ?
(D) What happens when MP3Tag stumbles upon a tag (like PURL (Podcast URL)) that is neither a TXXX tag nor one that it supports natively as described in the MP3Tag help (chapter "Names and mapping of ID3v2/WMA tag fields")? Is it discarded ? Or left untouched ?
(E) And maybe a last point: Does MP3Tag read+write the whole timestamp of TDOR and TDRC or only the year ? Because judging from the helpfile it is only linked to the year ....