It's hard to understand conversations if you're not a programmer; they're built just like rudimentary BASIC mini-programs. A condition is what must be tested, given any requested values, or arguments. All the conditions that can be tested (these are entered in the IF section of a line's info window; the conditions are the first field per line, and the respective arguments follow it):
1: true if player has (arg) coins or more
2: true if player has item of type (arg)
4: true if flag # (arg) is set (Used only within individual conversation)
5: true if player permflag # (arg) is set to (arg2) (Used gamewide)
If the condition(s) prove true, the conversation heads to the goto line specified in IF. If it is false (or if no conditions were specified beforehand), it a) executes any actions given it, and 
goes to the goto in ELSE. You cannot have a true IF statement while executing the actions in ELSE; you will need to goto a seperate line to do so. The actions that can be performed:
1: remove (arg) coins
2: give player item of type (arg) (arg2: how many)
(1: silver key, 2: gold key, 3: plat key, 4: magic potion, 5: health potion)
3: remove item of type (arg)
4: set permanent flag # (arg)
5: set player permflag # (arg) to (arg2)
(1, 2, or 3)
6: open rock barrier ((arg) = 0, (arg2) = 3; dunno why, but it works)
8: permanently validate sprite (arg) on level (arg2)
9: destroy this sprite permanently
If you want to execute a line's action(s) but not display its text, give a goto value with a negative sign preceding.
(This message has been edited by spamguy (edited 12-30-2000).)
but you posted what I interpret to say that you have to set the rock barrier you want to open to -2. If thats what you meant I think that is false, -2 in the INFO(0) makes the rock barrier open on a timer. To open a conversational rock barrier it doesn't need anything in any info field. It might not work with anything but nothing (in other words, something) in the info fields, but I haven't tried.