The analyses of a text #2

The narrator recalls his adolescence.
When Mr. Omer was smoking by parlour-door, he stopped by the local undertaker Mr. Omer's place before visiting his old nurse Peggotty's house for her husband Mr. Barkis' impending death.

..........................
'I am sorry to have heard bad news of Mr. Barkis,' said I.
Mr. Omer looked at me, with a steady countenance, and shook his head.
'Do you know how he is tonight?' I asked.
'The very question I should have put to you, sir,' returned Mr. Omer, 'but on account of delicacy. It's one of the drawbacks of our line of business. When a party's ill, we can't ask how the party is.'
The difficulty had not occurred to me; though I had had my apprehensions too, when I went in, of hearing the old tune. On its being mentioned, I recognized it, however, and said as much.
'Yes, yes, you understand,' said Mr. Omer, nodding his head. 'We dursn't do it. Bless you, it would be a shock that the generality of parties mightn't recover, to say "Omer and Joram's compliments, and how do you find yourself this morning?" - or this afternoon - as it may be.'
[David Copperfield by Charles Dickens]
1. I'd like to know what "party" means here.
2. I'd like to know what "my apprehensions of hearing the old tune" means.
3. I'd like to know if "to say" indicates the result of the parties' recover.
4. And I'd like to know what the greetings "someone's compliments" means.
Thank you in advance for your help.