This is very bothersome. This basically means whenever you change anything in the normal profile, it will carry over to the other profiles you have created.
The steps you laid out work perfectly well, Quentin. Just one correction, in step 9 the punctuation level will return to “none”, not to “all”.
This didn’t help with what I was trying to do though. I wanted to change the individual symbol level of some punctuations, but, as it turns out, individual symbol levels of punctuations are global settings. Andre Fisher is correct in this regard. For example, if you change the symbol level of left and right quotes in a new profile, it will carry over to the normal profile as well.
On the bright side, I realise, if you send the punctuations to the synthesizer in the punctuation and symbols dialogue box, and you have audio rules set for these punctuations in the Phonetic Punctuation add-on, then you will hear the set audio rule. So, effectively you can replace punctuations with audio sounds by sending the punctuations to the synthesizer without fiddling with the overall symbol level setting. This is what I was trying to do all this while. Got to learn a lot of things and finally managed to achieve the intended effect. Thank you guys!