For what it's worth, my two pyreals' worth ...
I mainly use LT only on my mages, and only in EO while I'm sitting there yakking in /a or to my hunting partner. I have noted the following things:
First, the mana issue IS new - when I was using version .2 I never had a problem with it. Since updating to the newer version? It is a constant issue, as is healing. I will also note I never received a CoC violation or boot when using version .2 at all.
Second, spellcasting is appreciably slower. Even version .2 in non-turbo mode was downright speedy compared to what is happening now.
Third, trying to manually override is far more difficult now than it was before. Not exactly sure why, however.
Is it possible that it is not the spellcasting itself that was causing problems, but the other options that many would turn on? For example, I don't have LT set to log me out, regardless of reasons you allow to be checked. I also do not have it logging tells and such (why bother? I'm there). I have unfriendly player detection turned off (I don't pk/pkl, so that is totally unnecessary for me). Could it possibly be one or a combo of these options that were causing issues? I find it hard to believe spellcasting alone was the issue.
As far as what plugins people are running? I've not changed a single plugin since this problem cropped up, and have received zero boots/violation notices. Maybe I'm just lucky, but I think some of these other options may be more to blame - in particular the unfriendly player detection, which I'd think would be scanning the immediate area quite a bit to find them? (When I've logged on a character that hasn't been logged on since the update, I have to manually turn it off, and the darn thing reports EVERYONE in the vicinity

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