RF questions related to AT86RF215

[bhj99]

Hi all, I plan on using the Mcirochip AT86RF215 part on a future project for SDR applications. I am looking at that AT86RF215 EVM refernce design schematic and, given my limited RF knowledge, I wanted to ask about why certain components/values were chosen. I would a better understanding, as I have the idea of leveraging the circuit design as much as possible. Attached is the schematic downloaded from Microchip.

More specifically:
1. On sheet 3, could anyone explain the values for C25, C10 were derived? Also, is R10 10Kohm pull-down needed for the TCXO clock output?
2. On sheet 3, how were all the cap and inductor values chosen for both sub-1GHz/2.4GHz RF paths (from AT86RF215 to balun and from balun to SMAs)? Also, how do the 10Kohm pull-downs (R10 & R11) serve as "ESD Protection" ?

Thanks in advance.