Ah, it's called "Embed Color Profile" on your version.
Sadly I don't know which are the good labs in Sydney. There must be plenty, though.
The classes are right here on the website.
Yes, it's perfect, great.
It should be right there, in the save dialog.
Do you mean in Photoshop? No, definitely not Custom. It must stay on "North America General Purpose 2".
Yes, Raw Class first.
Which part of Australia do you live?
Ok, can you choose the one with the least "busy" detail in it - eg clear sky and smooth water - and see if you get the same poor quality when you save?
http://www.damiensymonds.net/2015/08/about-jpeg-file-size.html
I know it is, that's exactly the point. You must NEVER sharpen in Lightroom.
It's just a plain blank layer. What's important is that you have your clone tool set to "Sample: Current and below" in the options bar.
There are two problems here. Both are very bad, but both are fixable.
The problem with them looking different is that in your Save As dialog, you don't have the "ICC profile" checkbox checked. It's really important to keep that checked at all times. Never uncheck it, under any circumstance.
The second problem is that you're in Adobe RGB. Follow this troubleshooter all the way to the end to fix this very very bad problem.
I beg you, don't wait too long to take the Sharpening class. Your edit makes me cry a little.
This is the best I can do:
It's not great, but I'm hoping it would pass casual scrutiny. What do you think?
The ppi is completely irrelevant. Generally we leave it at 300, but it honestly could be 10000, or 72, or 13. It's meaningless. Only the pixel dimensions matter.
PPI only matters when you're doing the printing yourself.
No, you didn't. You chose the instructions from the "Desktop computers and external monitors" column, but you have a Mac, so of course you were supposed to choose it from the "Macs and Laptops" column.