Im thinking of creating a dwarven crossbowman and run him through the BG-saga.
Im just wondering if the generic archer character-mod allows for the same bonuses for crossbows as it does for regular bows. Help please!

it does yes - enjoy . . .

Yes it does.

If you want to make the game ridiculously easy, install Improved Sahuagin City from the Tactics mod, and equip your guy with a Light X-Bow of Speed and those bolts. Probably make the game too easy, especially if you had a grandmastery fix.