@Fahim: Striders have that "life leech" skill (forgot the name), try using that as an attack skill, it will give you some +hp from time to time. Other than that your only possibility is to choose easier mobs I think, even if you don't level that fast. Think of it as an addition when you don't have time to play yourself.
And if you want your pet to assist you in attacking the mob, just put the "joined attack with your pet" on F1.
Edit: If you want your pet to attack
after you have attacked, try using the "creature attack" on one of the attack skills slots. I never tried that, but I'm pretty sure it will work.
@JT: First of all, I want to thank you for the time you take for coding this bot. Second, I have to say the bot works fine for me on XP. I only got the "error -1" one time in the beginning, it never appeared again, after I set the file options for the bot to "no archive" (or whatever it is called, I'm german...). The bot detection also works fine, at least with Megaloceros and those bunnies (once again, I forgot the name...). Edit2: I'm on the US servers.
Does this mean my OS is slowed down by a lot of garbage?