My Dad runs two pairs of CX100 + one Cona and a pair of redlines 60 from his Beomaster 4500, without any problems at all. Can play loud. The amp. should be about the same in your BC, so do not worry about an extra amp, unless you want to play very loud.
You should connect the CX in parallel to the MCL-2A.
Regarding the MCL cable: It is colorcoded and very easy to install, except for the soldering - which depends on your skills .
Living room: BV7-40 mkIV + V8000, BL5, BL3, BM1 and BS9000. Bedroom: MX3000 and BL4500 on MCL2-AV. Around: PentaIII, CX100 and MCX35 on ML/MCL + MCL2-A, BeoPort and BL4 on ML, BS3300 + M75 as stand alone, BC6000 + BC600 and BT1100, LC1, LC2, Beo4, Beo5 and BL1000, BS2 and A8, EarSet2, Apron, Coffee mugs, Enamel Bagdes, Bath towel, Keyring, Books, Lots of miniature and the Bottle opener. Office: BC2300 + BL2500 and BS3. Summer house: BS Century.
Addicted? Oh no.... ;)