It's a very old question, but if I found it, maybe someone else will come here, so here's what I found:

(I tested it with PIC12F615, Windows XP, PICDisasm 1.5, it worked, I still don't know if it's compatible with the current version of MPLABX, but it's already helped me a lot)

PICDisasm convert a Hex-File to a ASM-File.
The ASM-File is compatible to the Microchip-Assembler (MPLab-IDE). It works with PIC10, PIC12 and PIC16-Types.

The Windows-Program PICDisasm is Freeware.

• PICDisasm 1.6 (194 KByte) May,02 2008

• more details by commands: ADDLW, ANDLW, IORLW, MOVLW, RETLW, SUBLW, XORLW

• new PIC-Types added
  12F519
  16F526, 16F722, 16F723, 16F724, 16F726, 16F727

• some bugs fixed

• PICDisasm 1.5 (192 KByte) March,04 2007

• new PIC-Types added
  12F609, 12HV609, 12F615, 12HV615
  16F610, 16HV610, 16F616, 16HV616, 16F631, 16F677, 16HV785, 16F882, 16F883, 16F884, 16F886, 16F887

• PICDisasm 1.4 (192 KByte) March,23 2006

• new PIC-Types added
  10F220, 10F222, 12F510, 16F506, 16F946

• PICDisasm 1.3c (195 KByte) June,16 2005

• new PIC-Types added
  10F200, 10F202, 10F204, 10F206
  12F508, 12F509, 12F635
  16F59, 16F505, 16F636, 16F639, 16F685, 16F687, 16F689, 16F690, 16F785, 16F913, 16F914, 16F916, 16F917

• some bugs fixed

• PICDisasm 1.2 (243 KByte) May,7 2004

• new PIC-Types added
  12F683, 16F54, 16F57, 16F684, 16F688, 16F716

https://www.hagi-online.org/picmicro/picdisasm_en.html