(1) You can send messages in the Mac version of MA as Artanis described. Unfortunately, your messages are not readable by PC users...they just come through as garbled mess due to a bug. I am unsure whether Mac-to-Mac messages work properly or not. (Feel free to challenge 'Placid' with the map/army of your choosing and we'll give it a shot.
(2) You have probably experienced the "recruitment bug" found in the current Mac version of MA. I posted about this in the VP support forums, but apparently they just deleted these forums from their website entirely (maybe I was bugging them too much to get the their port of MA up to speed...). Well, in short, if you *disclose* a country after previously *recruiting* any unit(s) in any countries AND during the disclosure phase you un-click any unit(s) in order to delete them and make changes, THEN you will have to rewind back until the recruitment phase and redo all your recruits. If you don't rewind and redo, it will be as if you never bought anything. Thus, you might remember spending $2, but the next turn notice you have $2 extra and no recruit(s). This can obviously damage your game badly if you are absolutely counting on recruits to block a space, etc., so always check that to see if your recruits still exist before sending your turn...)