Rune rules question

I have two main questions:

First, I was wondering what exactly is meant on page 47 under "Actions, Half Actions and Free Rolls" by the phrase "plain, old, ordinary, unmodified attack roll, as well." Does this just mean no holding ground and ducking and weaving, or does it mean that terrain modifiers aren't taken into account? And if the latter is the case, what if there should be a negative modifier applied (e.g. combatant is at lower end of slope)? Also, does this "unmodified" attack apply if you have to move first to engage a foe? Last on this topic, is there a specific action cost (full, half, or other) that applies to attacks, holding ground and ducking and weaving, or does it change with the situation?

Secondly, heroes can't use a shield when holding a great or bow weapon, right? And, if that is the case, it seems like the shield scores shouldn't add to those weapon's INIT, ATK and DFN scores. Is this correct?

Thanks so much!

-Angrycorn

You can only use shields with single weapons.

An unmodified attack would imply there are no modifiers period.