Today I got again an error in mark 8.0 that seems to me like this one. I was trying to use the option "Replace data and Rerun models" from the main File menu, but it failed every time I tried to use it. Looking for the error log I found that its taking again Nbar as f0bar, so it says PIM was not specified correctly . The error log I got was this:
   Program  MARK  - Survival Rate Estimation with Capture-Recapture Data
   gfortran(Win32) Vers. 8.0 Jun 2014    7-Nov-2014 15:07:18    Page  001
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   This version was compiled by GCC version 4.8.1 using the options 
   -m32 -mtune=generic -march=x86-64 -mthreads -O2 -fimplicit-none -fbounds-check -funroll-loops -ftree-vectorize -fopenmp.
   This problem will use 1 of 1 possible threads.
  INPUT --- proc title 2013 IELNE hammherhead sharks;
     CPU Time in seconds for last procedure was 0.00
  INPUT --- proc chmatrix occasions=15 groups=1 etype=IELogitNormalMR 
  INPUT --- hist=300 NoHist;
  INPUT ---    glabel(1)=Group 1;
  INPUT ---    time interval 0 0 1 0 0 1 0 0 1 0 0 1 0 0;
   * *  WARNING  * *   At least a pair of the encounter histories are duplicates. 
      Number of unique encounter histories read was 18.
      Number of individual covariates read was 0.
      Time interval lengths vary and/or not equal to 1.
      Data type number is 120
      Data type is Immigration-Emigration Logit-Normal Mark Resight                                                    
     CPU Time in seconds for last procedure was 0.00
  Program  MARK  - Survival Rate Estimation with Capture-Recapture Data
   gfortran(Win32) Vers. 8.0 Jun 2014    7-Nov-2014 15:07:18    Page  002
   2013 IELNE hammherhead sharks                                               
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  INPUT --- /* End Input File */
  INPUT ---  proc estimate link=Logit varest=2ndPart;
  INPUT --- model={p(.) sigma(.) nbar(s) alpha(.) nstar(.) none inipar};
  INPUT ---    group=1 p Session 1 rows=1 cols=3 Square Constant=1;
  INPUT ---    group=1 sigma Session 1 rows=1 cols=1 Square Constant=2;
  DATTYP =          120
 group                         =                             1                             f0bar                         Session                       1                             rows                          =                             1                             cols                          =                             1                             Square                        Constant                      =                             3                             
     Parameter specified was not one of the recognized parameters:
     a', a'', alpha, c, d, delta, epsilon, epsilonA, epsilonAB, epsilonB, epsilonBA,
     f, F, F', f0, gamma, gamma', gamma'', gammaA, gammaAB, gammaB, gammaBA, lambda,
     M, N, Nbar, Nstar, omega, p, p1, p2, pA, pB, pent, phi, phi0, pi,
     psi, psi1, psi2, psiA, psiAB, psiB, psiBA, psiBa, ptilde, R, R', r, rA,
     rAB, rAb, raB, rBA, rBa, S, sigma, sigmaf, sigmap, sigmaphi, sigmar, sigmaS,
     theta, theta', U, or VarAdd
  INPUT ---    group=1 f0bar Session 1 rows=1 cols=1 Square Constant=3;
 ERROR -- Type of Parameter Input Matrix (PIM) was not specified correctly.
Hope it helps...