PSoC Creator 2.1 has new components called bootloader and bootloadable.
All new bootloadable projects are compatible with older version of bootloader.
Say the bootloadable project is built with Creator 2.1 using Bootloadable component v1.0 this is compatible with older bootloader projects.
But important to note is that ,
-Say you had created a bootloader project previously using USB bootloader(in previous creator versions bootloader was embedded inside the comm. component like USB, I2C) in Creator 2.0 and programmed the device. Now you need to update or write the bootloadable project , then in the Creator 2.1 the dependency of bootloadable project should point to bootloader project which is programmed in the device.i.e, Bootloader project created in 2.0 but not to create new bootloader project in Creator 2.1 and point dependency of bootloadable to new bootloader.
If you try bootloading the device having older bootloader with new bootloadable poinitng to new bootloader will generate error.
Thanks! That is important to knwo, because I use bootloader/bootloadable quite extensively in my projects.