Correct Deity Salutations In General & Gujarati - Help Needed!

Hello All,

I am hoping someone with expert knowledge can help advise on a few things - STRICTLY, when is it correct to use Aum/Om or Jai/Jai-Shri when addressing Dieties?

For example, when addressing Shiva, we always say "Aum" Namah Shivaya but never "Jai" Shiva or "Jai Shri" Shiva.

Conversely, when referring for example to say Krishna or Rama, we always say “Jai Shri" Krishna or “Jai” Ram/"Hey" Ram but never “Aum” Krishna/“Aum” Namah Krishna / "Aum" Ram / "Aum Shri" Ram etc.

Why is this? Why does Shiva (& some others I understand) qualify for an Aum & other Dieties a Jai/Jai Shri?
Also, when is it appropriate to use just a "Jai" & when a "Jai Shri"?

I would like to know & it must be absolutely correct in terms of what the scriptures or Dharma states on how to address the Deity “Srinathji and/or Shriji-Baba” - Is it:

a) Aum Shrinathji
b) Aum Shri Shrinathji
c) Jai Shrinathji
d) Jai Shri Shrinathji
e) Other - if so, what?

I was told by one religious person from a temple that “Aum” is strictly to be used for particular & specific Dieties only & must not to be used as a general salutation to any others. On the other hand, another religious person from another temple else told me that is OK to do so so I am very confused!

2) When Googling, I found many different versions stated below from different sources so if one were to write this in an Indic script like Gujarati, after Aum, would it all be one single word or 3 separate words? Which of the following is correct:

a) Aum Satchitananda
b) Aum Sat Chit Ananda

c) Aum Satcitananda
d) Aum Sat Cit Ananda

e) Aum Satchidananda
f) Aum Sat Chid Ananda

g) Aum Satchidaananda
h) Aum Sat Chida Ananda

i) Other - if so, what? (Should there be any Caplitalizations?)

How would one write the correct version/way in Gujarati please? I am mindful that like in the Japanese scripts, even an extremely minor change/error may cause a very big change or can cause something to mean something else which is why I wish to make sure.

3) If anyone is fluent in the Gujarati script, please can you tell me the religiously correct way to write "Aum Namah Shivaya" in Gujarati? I have tried a number of Online English to Gujarati Translation websites but there seem to some differences between them - the results generated were:

a) ॐ નમહ શિવાય
b) ઓમ નમહ શિવાય
c) ઓમ નમ શિવાય
d) ઓમ નમ: શિવાય

If none are correct, please let me know what is!

Apologies for my ignorance on the matter! Many Thanks & hoping some kind folks here can help & clarify with certainty things for me!

Bazzy!