Protection error issue can be solved by downloading the dump file, see here:
http://www.twcenter.net/forums/showthread.php?t=61071

Why on earth there are no more topics about this?

I am no expert in British history, but at least it feels that this is the most historically accurate portrait of Britannian wars during the true dark ages, 400-700 AD. Never seen that detailed and huge playable map of ancient Britannia in any game. Ireland is also a large battlefield. All the reworked units and with new names seems damn imperssive.

What was more surprising that mod is 0.6, but relatively bug free. Unfotunately, I can't continue my Angles campaign since it's always CTD during Dal Riada turn in summer of 503 AD.

I can imagine that if this mod reaches 1.0, it will be easily one of the best mods in RTW and certainly the best and with BI. Arthurian TW is for me the same improvment over BI as 'Europa Barbarorum' and 'Rome Total Realism' are over RTW. Absolutely brilliant mod!
Thanks for you feedback
And for reporting this CTD... we were hoping 0.6 was CTD free, we got lot of issues with 0.62 patch, and I hope everything will be right for the upcoming 0.7 version!