If tracker contains a 'warning message' in its answer - Tixati won't show it or react on it.
Some trackers put valuable info in such messages, like "torrent not registered".

I am not sure what you mean that "tixati won't show or react on it"

From Tixati/Transfers/ Layout = Tab View  /Tab = Trackers, 3 columns are displayed
Group
URL
Status

For one of my active torrents, 1 tracker is reporting in Status tab:  Tracker fail: Torrent not registered with this tracker. Retry in 45:10

When I see that, I manually remove the URL for that tracker.

When "Host not found" is reported, I usually make an entry in /Settings/Transfers/Trackers/New Tracker Adjustment/1. Remove tracker URLs containing: < add failed host URL>

If host can't be found, it usually means that hostname is no longer registered in the DNS, seldom to return

It would be nice for tixati to have 'react' options for the common pre-defined conditions like:
"Host not found" - stop announcing for xx days, 0 = infinity,
"torrent not registered" - after x days (to allow for uploading time after user creates a new torrent, delay announcing to xx days -
"Timed out" - after 3rd/10th attempt, reduce announce frequency to xx days
"Connection refused"  same
password required - ?

I mean it literally. Tixati ignores such messages from a tracker. It shows torrent status as OK on trackers tab. But uTorrent shows the same torrent as 'not registered'.

There is an example of such answer from tracker:

GET /ann?uk=xxxxxxx&info_hash=xxxxxxxxxxxxxxxxxxxxxxxxx&peer_id=xxxxxxxxxxxxxxxxx&key=xxxxx&compact=1&port=xxx&uploaded=8160300&downloaded=0&left=7470945 HTTP/1.1
User-Agent: rtorrent/0.9.4/0.13.4
Host: xxxxxxxxxxx
Accept: */*
Accept-Encoding: deflate, gzip

HTTP/1.1 200 OK
Content-Type: text/plain
Pragma: no-cache
Transfer-Encoding: chunked
Date: Wed, 14 Jan 2015 20:03:11 GMT
Server: lighttpd/1.4.35

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d8:intervali3411e12:min intervali3411e5:peers6:^.$Q..15:warning message22:Torrent not registerede
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