If you don't know how any of the mods work, open 200_to_201.pack with mabiunpack or something and delete all the xml and db text files that were updated.
Crackshield and Abyss are both working fine.
I'm saying specifically the Tiara mod package (as a whole) may not be working currently (for R201). I understand how to apply the mods and un-apply the mods with datapacker and also abyss.ini. The abyss and crackshield programs may be working properly but something isn't when you have a tiara modded mabinogi R201. The completely unmodded mabinogi post R201 works just fine.
I understand how to install Tiara package also (got it to work before R201). Run installer, check mods you want, install to mabinogi folder, run abyss.ini to set preferences, run datapacker to modify files, run crackshield, run client. So my modded mabinogi worked just fine before R201; after the R201 patch it won't work anymore. I also patched to R201 (without crackshield on while patching of course), ran things at admin, used the modded launcher, repatched by deleting language.pack, made sure to be running crackshield when trying to get launch the R201 client. The bar stops just shy of the end of the Pleione Engine initialization so you cannot log in and play the game. The client still shows it is modded (tiara icon, abyss options, etc.) and has no hackshield error or anything.
So I tried to see if this was caused by Tiara mod package. I first used datapacker to remove the mod files (restore). And then i ran the uninstaller for tiara (uninstalled everything). Test ran client, still had problems (although this happens often after uninstalling tiara). So I went to my backup unmodded mabinogi, made another copy, patched the copy to R201, test ran client, worked just fine (no Pleione Engine initialization issues). Then I installed Tiara on the patched R201 copy. Did all the installation process as stated above. Test ran the client, Pleione Engine initialization problem again.
So I'm in no a technician on this but I'm just putting it out there that there MAY be a need to update Tiara for it to work with post R201. So hopefully a certified mabimods technician or shaggyze can look into it :x
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As for your reply, I'm assuming you mean somewhere along the lines of "the patch files may have overwritten some of the mod db/xml files and thus are causing problems"?
I know you may have to run datapacker again after patches so i tried that. Still didn't work.
Also tried making sure to save all the pre patch xml/db files from Tiara pre-R201, patched R201, and then readding/overwriting the new ones with the pre-R201 versions. Still didn't work.
The only way I've gotten past the Pleione Engine initialization issue is to run a completely clean mabinogi.