i'm not really sure what exactly the code is doing but the highlighted sections are doing something with the label but ignoring the upper byte of its address. below 64k its not an issue i would not say its bug , more like its not designed to be relocated beyond the 64k boundary.
anyways its the only thing i see in the code thats likely to be an issue.



Code:
01EE52 0E04               M         movlw   low (low (HSEROUT2J))MPASM 5.61                          MCKD.ASM   1-30-2021  23:44:34         PAGE 32




LOC  OBJECT CODE     LINE SOURCE TEXT
  VALUE


01EE54 6E0A               M         movwf   R8
                          M       endif
                          M     endif
                          M         MOVE?CB high (HSEROUT2J), (R8) + 1
                          M         CHK?RP  (R8) + 1
                          M     if ((((R8) + 1) & 8000h) != PREV_ALT)
                          M       if (((R8) + 1) & 8000h)
                          M         bsf     WDTCON, ADSHR
                          M       else
                          M         bcf     WDTCON, ADSHR
                          M       endif
                          M PREV_ALT = ((R8) + 1) & 8000h
                          M     endif
                          M     if (((((R8) + 1) & 0fffh) > BANKA_END) & ((((R8) + 1) & 0fffh) < (0f01h + BANKA_END)))
                          M       if ((((R8) + 1) & 0f00h) != (PREV_BANK << 8))
                          M         movlb   high ((R8) + 1)
                          M PREV_BANK = high ((R8) + 1)
                          M       endif
                          M     endif
                          M     if (low (high (HSEROUT2J)) == 0)
                          M         clrf    (R8) + 1
                          M     else
                          M       if (low (high (HSEROUT2J)) == 255)
                          M         setf    (R8) + 1
                          M       else
01EE56 0EEC               M         movlw   low (high (HSEROUT2J))
01EE58 6E0B               M         movwf   (R8) + 1