Triple Boot Problems?

I finally Dual Booted XP and Xandros, and it works perfectly...so i tryed Triple booting a few OS's. First i tried Freespire, deleted because it didnt work, then i tried ubuntu, also didnt work, and now i just installed CentOS and IT doesent work. Im using bootpart to dual boot the systems. How come Xandros works fine but when i triple boot an os, i click the os, and it just says Loading New Partition and the cursor blinks or Unable To Load Please Insert System Disk?