- How can I tell a unit which weapon to attack with? (if that's possible)
You primarily don't they only have one weapon basically. They do have special abilities like preist has heal and such. When it is there turn look in lower right of screen. There will be icons for each special ability the unit has. click it then target to perform it.
- If I don't want to move a unit, how do I select the next unit instead?
You can either tell it to guard, or wait. (Also in bottom right of screen, hour glass is wait and shield is guard or possibly defend not sure term)
Wait will make the unit perform it's turn after everyone else.
Guard will give them extra defense if they are attacked.
- Do I have to move a unit to it's maximum range? Or can I move it just a few steps within its range and then select the next unit.
Yes, you can move one step and then either wait or guard and it'll go to next unit. You do not get to select who is next. This is determined by the units initiative compared to everyone else. You can hold down alt or shift and left click to get this info of what the turn order is...
Suggestions.... Hmmm so far, just be careful if not playing on easy. You can right click a stack and see is stretngth comparison to yours ranging form very weak to impossible. Even in beginning area a couple are impossible at first. Note this is just a guide line also, some creatures are just easier to take on. You'll learn that though, just stick with anything below match at first.
The dragon in tutorial is a tough fight, must creatures won't last as long after the tutorial until you get to harder areas. Though your army will be weaker also
Edit: I think there is also a nice FAQ in this dorum for first time players, read it
("Top 10 tips for everybody starting the game! (non-spoiler)" sticky in tips and hint ummm
http://forum.1cpublishing.eu/showthread.php?t=3957)