The tutorial you linked KitKat is indeed what you are looking for, although the blender part can now also be done in Studio itself. So to fix this you first need to open the candle in Studio, then go the rig/slots tab. If there isn't one, you need to exit Studio again and first place the Custom candle package into your mods folder of The Sims 4 Studio. (So NOT the games mod folder) The Mod folder of the Sims 4 Studio can also be found in your documents folder > The Sims 4 Studio > Mods
Then start Studio again, click on "Create 3D Mesh/Selective clone", for type select "Custom" and then choose the custom candle. Now there should be a rigs/slots tab in Studio too. In this section you can change the position of the effect slot, which is now probably somewhere in the middle.
You can use the Slot Editor tutorial probably too at this point. Just be aware this is about deco slots and not the FX slots. You will have to change the FX slot for the flame.
Yes - the candle with multiple flames tutorial did the trick! Just delete the extra candle flame _FX_ rig/bones in Studio to the number you need.
bakie - what did you mean being able to do the Blender part in Studio now? Is there a way to find the precise Z height inside Studio, or do you just have to guesstimate?
Well, you can just try by filling in other numbers in the Z line in the rigs/slots tab, you will see the FX slot in the object viewer moving. Or you can use blender, but only for looking at the place of the flame of the candle should be and then filling in those numbers in Studio's rigs/slots tab.
To be more clear, I'm talking about the rigs and slot TAB not the sections in the warehouse. You can see what I mean by looking at the slots tutorial I linked.
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