*D3nb3r: actually, the tuning you can do is limited to what your equipment can offer. it follows that the user manual will only cover what the actual equipment is capable of.

for the p300.2 amp, there is nothing you need to adjust but the Gain. for sure you will use All Pass mode since you're connecting separates. if you have a subwoofer, you can opt to use High Pass mode for the separates and set the cut-off point between subwoofer and separates.

for the Polk Momo speakers, there is nothing again to adjust since it uses passive crossover. you can only attenuate the level of the tweeters (0, -3dB, -6dB) but you can't adjust crossover frequency between mid-bass and tweeter.