Glad to see you agree on that point then
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The PW2 is a completely different beast from other models, so while technically still falling under the K5 family, it does need special attention, depending on exactly what the app/script does. And since a lot of the stuff you mentioned have been developed/last updated well before the PW2 appeared, that's not terribly surprising.
AFAIR, the original weather stuff was done on a K4, I don't quite see how you ended up thinking of K4A? Anyway, that's pretty straightforward stuff, and it should be fairly portable with a minimum of effort if need be. And I even think the last time this was discussed (fairly recently) was on K5 devices.
And yeah, I can assure eyou that the light definitely has nothing to do with the JB. The JB has one job only, and that's letting you install custom OTA packages, period. On the other hand, there's probably scripts to control the light further (besides in-app control for full readers like KOReader or CR), but that's, well, completely separate from the JB
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