I'm running Redhat 7.2. The rp3 dialer works fine to connect me to my ISP. I used to use an application called Modem Lights via a launcher on my panel to dial up before my connection mysteriously stopped functioning one day. After much experimenting I changed comm ports, started from scratch using rp3 config and began using the rp3 dialer.

Now when I connect using rp3 dialer, Modem Lights still graphically monitors data flow over the connection like it used to. However it will not dial up the connection or stop it. I would like to get the Modem Lights launcher working again. In the general settings for Modem Lights it has fields that are currently configured as follows;

Connect command: /sbin/ifup ppp0
Disconnect command: /sbin/ifup ppp0

The advanced settings are configured as follows;

Modem Lock File : /var/lock/LCK.ttyS1
Device: ppp0

These settings are mostly a legacy from when I had Modem Lights installed by someone else a couple of years ago, and before I changed my comm port (using ttyS1 now) and dial up configuration using rp3 config. I have fiddled with these settings a few times so I may have made some changes.
I thought if I could just put whatever commands the rp3 dialer now uses to dialup into these fields of the Modem Lights settings, I could go back to using the Modem Lights launcher to dialup.

Q1) What should I put in these fields of Modem Lights settings so I can use its launcher to dialup instead of the rp3 dialer?

I also notice that when dialing up using rp3 dialer I am asked to choose an interface from a list as follows;

ppp0
myISP (the only one I use)
ppp9
eth0 (I have a network card)
loopback

Q2) How can I make myISP the default interface so I don't have to scroll down this list and select it each time I dial up when using rp3 dialer?
Q3) What are the ppp0, ppp9 & loopback intefaces for anyway?