Regarding ability damage, in most cases this is temporary and recovers with rest. You would probably want to transfer any ability score damage to your character sheet at the end of combat since the CT effect will go away the next time you rest. I don't know how people are doing this now - I have just handled it manually by rolling dice from the desktop and applying to the character sheet.
The random effect durations will be nice I think, but I need to do more testing. One of the things I struggle with is the complexity of spell effects. The number of possible effects can be overwhelming, and in many cases, the only difference is the duration. Currently, the parse data that auto-populates spell effects on the char sheet does not specify a duration if it's random, which simplifies things in a way. Adding this feature might lead to several more effects populating under a spell. See below...
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