PBP RAM allocation - how to find available or total used RAM?

[richard]

But what about RAM? PBP manual says, arrays are limited to 96 bytes on PIC16 series. I guess this is related to amount of free ram.

some pic16 are limited to 80 bytes, its not about free sram but due to the fact that pbp uses "banking" to access the sram, the limit is the amount of gp ram available in a bank.
arrays of much larger size can be used with linear memory access [you will not be interested since the word asm is involved]

And if my array uses 72 bytes, will be there ram left for other my code? I mean, the code might compile to 2-3kb, but there will be no RAM to run additional code. Is such situation possible?

absolutely